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1/*
2 * Neighbour Discovery for IPv6
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Mike Shaver <shaver@ingenia.com>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 */
14
15/*
16 * Changes:
17 *
18 * Alexey I. Froloff : RFC6106 (DNSSL) support
19 * Pierre Ynard : export userland ND options
20 * through netlink (RDNSS support)
21 * Lars Fenneberg : fixed MTU setting on receipt
22 * of an RA.
23 * Janos Farkas : kmalloc failure checks
24 * Alexey Kuznetsov : state machine reworked
25 * and moved to net/core.
26 * Pekka Savola : RFC2461 validation
27 * YOSHIFUJI Hideaki @USAGI : Verify ND options properly
28 */
29
30#define pr_fmt(fmt) "ICMPv6: " fmt
31
32#include <linux/module.h>
33#include <linux/errno.h>
34#include <linux/types.h>
35#include <linux/socket.h>
36#include <linux/sockios.h>
37#include <linux/sched.h>
38#include <linux/net.h>
39#include <linux/in6.h>
40#include <linux/route.h>
41#include <linux/init.h>
42#include <linux/rcupdate.h>
43#include <linux/slab.h>
44#ifdef CONFIG_SYSCTL
45#include <linux/sysctl.h>
46#endif
47
48#include <linux/if_addr.h>
49#include <linux/if_ether.h>
50#include <linux/if_arp.h>
51#include <linux/ipv6.h>
52#include <linux/icmpv6.h>
53#include <linux/jhash.h>
54
55#include <net/sock.h>
56#include <net/snmp.h>
57
58#include <net/ipv6.h>
59#include <net/protocol.h>
60#include <net/ndisc.h>
61#include <net/ip6_route.h>
62#include <net/addrconf.h>
63#include <net/icmp.h>
64
65#include <net/netlink.h>
66#include <linux/rtnetlink.h>
67
68#include <net/flow.h>
69#include <net/ip6_checksum.h>
70#include <net/inet_common.h>
71#include <linux/proc_fs.h>
72
73#include <linux/netfilter.h>
74#include <linux/netfilter_ipv6.h>
75
76static u32 ndisc_hash(const void *pkey,
77 const struct net_device *dev,
78 __u32 *hash_rnd);
79static bool ndisc_key_eq(const struct neighbour *neigh, const void *pkey);
80static int ndisc_constructor(struct neighbour *neigh);
81static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
82static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
83static int pndisc_constructor(struct pneigh_entry *n);
84static void pndisc_destructor(struct pneigh_entry *n);
85static void pndisc_redo(struct sk_buff *skb);
86
87static const struct neigh_ops ndisc_generic_ops = {
88 .family = AF_INET6,
89 .solicit = ndisc_solicit,
90 .error_report = ndisc_error_report,
91 .output = neigh_resolve_output,
92 .connected_output = neigh_connected_output,
93};
94
95static const struct neigh_ops ndisc_hh_ops = {
96 .family = AF_INET6,
97 .solicit = ndisc_solicit,
98 .error_report = ndisc_error_report,
99 .output = neigh_resolve_output,
100 .connected_output = neigh_resolve_output,
101};
102
103
104static const struct neigh_ops ndisc_direct_ops = {
105 .family = AF_INET6,
106 .output = neigh_direct_output,
107 .connected_output = neigh_direct_output,
108};
109
110struct neigh_table nd_tbl = {
111 .family = AF_INET6,
112 .key_len = sizeof(struct in6_addr),
113 .protocol = cpu_to_be16(ETH_P_IPV6),
114 .hash = ndisc_hash,
115 .key_eq = ndisc_key_eq,
116 .constructor = ndisc_constructor,
117 .pconstructor = pndisc_constructor,
118 .pdestructor = pndisc_destructor,
119 .proxy_redo = pndisc_redo,
120 .id = "ndisc_cache",
121 .parms = {
122 .tbl = &nd_tbl,
123 .reachable_time = ND_REACHABLE_TIME,
124 .data = {
125 [NEIGH_VAR_MCAST_PROBES] = 3,
126 [NEIGH_VAR_UCAST_PROBES] = 3,
127 [NEIGH_VAR_RETRANS_TIME] = ND_RETRANS_TIMER,
128 [NEIGH_VAR_BASE_REACHABLE_TIME] = ND_REACHABLE_TIME,
129 [NEIGH_VAR_DELAY_PROBE_TIME] = 5 * HZ,
130 [NEIGH_VAR_GC_STALETIME] = 60 * HZ,
131 [NEIGH_VAR_QUEUE_LEN_BYTES] = SK_WMEM_MAX,
132 [NEIGH_VAR_PROXY_QLEN] = 64,
133 [NEIGH_VAR_ANYCAST_DELAY] = 1 * HZ,
134 [NEIGH_VAR_PROXY_DELAY] = (8 * HZ) / 10,
135 },
136 },
137 .gc_interval = 30 * HZ,
138 .gc_thresh1 = 128,
139 .gc_thresh2 = 512,
140 .gc_thresh3 = 1024,
141};
142EXPORT_SYMBOL_GPL(nd_tbl);
143
144void __ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data,
145 int data_len, int pad)
146{
147 int space = __ndisc_opt_addr_space(data_len, pad);
148 u8 *opt = skb_put(skb, space);
149
150 opt[0] = type;
151 opt[1] = space>>3;
152
153 memset(opt + 2, 0, pad);
154 opt += pad;
155 space -= pad;
156
157 memcpy(opt+2, data, data_len);
158 data_len += 2;
159 opt += data_len;
160 space -= data_len;
161 if (space > 0)
162 memset(opt, 0, space);
163}
164EXPORT_SYMBOL_GPL(__ndisc_fill_addr_option);
165
166static inline void ndisc_fill_addr_option(struct sk_buff *skb, int type,
167 void *data, u8 icmp6_type)
168{
169 __ndisc_fill_addr_option(skb, type, data, skb->dev->addr_len,
170 ndisc_addr_option_pad(skb->dev->type));
171 ndisc_ops_fill_addr_option(skb->dev, skb, icmp6_type);
172}
173
174static inline void ndisc_fill_redirect_addr_option(struct sk_buff *skb,
175 void *ha,
176 const u8 *ops_data)
177{
178 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, ha, NDISC_REDIRECT);
179 ndisc_ops_fill_redirect_addr_option(skb->dev, skb, ops_data);
180}
181
182static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur,
183 struct nd_opt_hdr *end)
184{
185 int type;
186 if (!cur || !end || cur >= end)
187 return NULL;
188 type = cur->nd_opt_type;
189 do {
190 cur = ((void *)cur) + (cur->nd_opt_len << 3);
191 } while (cur < end && cur->nd_opt_type != type);
192 return cur <= end && cur->nd_opt_type == type ? cur : NULL;
193}
194
195static inline int ndisc_is_useropt(const struct net_device *dev,
196 struct nd_opt_hdr *opt)
197{
198 return opt->nd_opt_type == ND_OPT_RDNSS ||
199 opt->nd_opt_type == ND_OPT_DNSSL ||
200 ndisc_ops_is_useropt(dev, opt->nd_opt_type);
201}
202
203static struct nd_opt_hdr *ndisc_next_useropt(const struct net_device *dev,
204 struct nd_opt_hdr *cur,
205 struct nd_opt_hdr *end)
206{
207 if (!cur || !end || cur >= end)
208 return NULL;
209 do {
210 cur = ((void *)cur) + (cur->nd_opt_len << 3);
211 } while (cur < end && !ndisc_is_useropt(dev, cur));
212 return cur <= end && ndisc_is_useropt(dev, cur) ? cur : NULL;
213}
214
215struct ndisc_options *ndisc_parse_options(const struct net_device *dev,
216 u8 *opt, int opt_len,
217 struct ndisc_options *ndopts)
218{
219 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
220
221 if (!nd_opt || opt_len < 0 || !ndopts)
222 return NULL;
223 memset(ndopts, 0, sizeof(*ndopts));
224 while (opt_len) {
225 int l;
226 if (opt_len < sizeof(struct nd_opt_hdr))
227 return NULL;
228 l = nd_opt->nd_opt_len << 3;
229 if (opt_len < l || l == 0)
230 return NULL;
231 if (ndisc_ops_parse_options(dev, nd_opt, ndopts))
232 goto next_opt;
233 switch (nd_opt->nd_opt_type) {
234 case ND_OPT_SOURCE_LL_ADDR:
235 case ND_OPT_TARGET_LL_ADDR:
236 case ND_OPT_MTU:
237 case ND_OPT_NONCE:
238 case ND_OPT_REDIRECT_HDR:
239 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
240 ND_PRINTK(2, warn,
241 "%s: duplicated ND6 option found: type=%d\n",
242 __func__, nd_opt->nd_opt_type);
243 } else {
244 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
245 }
246 break;
247 case ND_OPT_PREFIX_INFO:
248 ndopts->nd_opts_pi_end = nd_opt;
249 if (!ndopts->nd_opt_array[nd_opt->nd_opt_type])
250 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
251 break;
252#ifdef CONFIG_IPV6_ROUTE_INFO
253 case ND_OPT_ROUTE_INFO:
254 ndopts->nd_opts_ri_end = nd_opt;
255 if (!ndopts->nd_opts_ri)
256 ndopts->nd_opts_ri = nd_opt;
257 break;
258#endif
259 default:
260 if (ndisc_is_useropt(dev, nd_opt)) {
261 ndopts->nd_useropts_end = nd_opt;
262 if (!ndopts->nd_useropts)
263 ndopts->nd_useropts = nd_opt;
264 } else {
265 /*
266 * Unknown options must be silently ignored,
267 * to accommodate future extension to the
268 * protocol.
269 */
270 ND_PRINTK(2, notice,
271 "%s: ignored unsupported option; type=%d, len=%d\n",
272 __func__,
273 nd_opt->nd_opt_type,
274 nd_opt->nd_opt_len);
275 }
276 }
277next_opt:
278 opt_len -= l;
279 nd_opt = ((void *)nd_opt) + l;
280 }
281 return ndopts;
282}
283
284int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
285{
286 switch (dev->type) {
287 case ARPHRD_ETHER:
288 case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */
289 case ARPHRD_FDDI:
290 ipv6_eth_mc_map(addr, buf);
291 return 0;
292 case ARPHRD_ARCNET:
293 ipv6_arcnet_mc_map(addr, buf);
294 return 0;
295 case ARPHRD_INFINIBAND:
296 ipv6_ib_mc_map(addr, dev->broadcast, buf);
297 return 0;
298 case ARPHRD_IPGRE:
299 return ipv6_ipgre_mc_map(addr, dev->broadcast, buf);
300 default:
301 if (dir) {
302 memcpy(buf, dev->broadcast, dev->addr_len);
303 return 0;
304 }
305 }
306 return -EINVAL;
307}
308EXPORT_SYMBOL(ndisc_mc_map);
309
310static u32 ndisc_hash(const void *pkey,
311 const struct net_device *dev,
312 __u32 *hash_rnd)
313{
314 return ndisc_hashfn(pkey, dev, hash_rnd);
315}
316
317static bool ndisc_key_eq(const struct neighbour *n, const void *pkey)
318{
319 return neigh_key_eq128(n, pkey);
320}
321
322static int ndisc_constructor(struct neighbour *neigh)
323{
324 struct in6_addr *addr = (struct in6_addr *)&neigh->primary_key;
325 struct net_device *dev = neigh->dev;
326 struct inet6_dev *in6_dev;
327 struct neigh_parms *parms;
328 bool is_multicast = ipv6_addr_is_multicast(addr);
329
330 in6_dev = in6_dev_get(dev);
331 if (!in6_dev) {
332 return -EINVAL;
333 }
334
335 parms = in6_dev->nd_parms;
336 __neigh_parms_put(neigh->parms);
337 neigh->parms = neigh_parms_clone(parms);
338
339 neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
340 if (!dev->header_ops) {
341 neigh->nud_state = NUD_NOARP;
342 neigh->ops = &ndisc_direct_ops;
343 neigh->output = neigh_direct_output;
344 } else {
345 if (is_multicast) {
346 neigh->nud_state = NUD_NOARP;
347 ndisc_mc_map(addr, neigh->ha, dev, 1);
348 } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
349 neigh->nud_state = NUD_NOARP;
350 memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
351 if (dev->flags&IFF_LOOPBACK)
352 neigh->type = RTN_LOCAL;
353 } else if (dev->flags&IFF_POINTOPOINT) {
354 neigh->nud_state = NUD_NOARP;
355 memcpy(neigh->ha, dev->broadcast, dev->addr_len);
356 }
357 if (dev->header_ops->cache)
358 neigh->ops = &ndisc_hh_ops;
359 else
360 neigh->ops = &ndisc_generic_ops;
361 if (neigh->nud_state&NUD_VALID)
362 neigh->output = neigh->ops->connected_output;
363 else
364 neigh->output = neigh->ops->output;
365 }
366 in6_dev_put(in6_dev);
367 return 0;
368}
369
370static int pndisc_constructor(struct pneigh_entry *n)
371{
372 struct in6_addr *addr = (struct in6_addr *)&n->key;
373 struct in6_addr maddr;
374 struct net_device *dev = n->dev;
375
376 if (!dev || !__in6_dev_get(dev))
377 return -EINVAL;
378 addrconf_addr_solict_mult(addr, &maddr);
379 ipv6_dev_mc_inc(dev, &maddr);
380 return 0;
381}
382
383static void pndisc_destructor(struct pneigh_entry *n)
384{
385 struct in6_addr *addr = (struct in6_addr *)&n->key;
386 struct in6_addr maddr;
387 struct net_device *dev = n->dev;
388
389 if (!dev || !__in6_dev_get(dev))
390 return;
391 addrconf_addr_solict_mult(addr, &maddr);
392 ipv6_dev_mc_dec(dev, &maddr);
393}
394
395static struct sk_buff *ndisc_alloc_skb(struct net_device *dev,
396 int len)
397{
398 int hlen = LL_RESERVED_SPACE(dev);
399 int tlen = dev->needed_tailroom;
400 struct sock *sk = dev_net(dev)->ipv6.ndisc_sk;
401 struct sk_buff *skb;
402
403 skb = alloc_skb(hlen + sizeof(struct ipv6hdr) + len + tlen, GFP_ATOMIC);
404 if (!skb) {
405 ND_PRINTK(0, err, "ndisc: %s failed to allocate an skb\n",
406 __func__);
407 return NULL;
408 }
409
410 skb->protocol = htons(ETH_P_IPV6);
411 skb->dev = dev;
412
413 skb_reserve(skb, hlen + sizeof(struct ipv6hdr));
414 skb_reset_transport_header(skb);
415
416 /* Manually assign socket ownership as we avoid calling
417 * sock_alloc_send_pskb() to bypass wmem buffer limits
418 */
419 skb_set_owner_w(skb, sk);
420
421 return skb;
422}
423
424static void ip6_nd_hdr(struct sk_buff *skb,
425 const struct in6_addr *saddr,
426 const struct in6_addr *daddr,
427 int hop_limit, int len)
428{
429 struct ipv6hdr *hdr;
430 struct inet6_dev *idev;
431 unsigned tclass;
432
433 rcu_read_lock();
434 idev = __in6_dev_get(skb->dev);
435 tclass = idev ? idev->cnf.ndisc_tclass : 0;
436 rcu_read_unlock();
437
438 skb_push(skb, sizeof(*hdr));
439 skb_reset_network_header(skb);
440 hdr = ipv6_hdr(skb);
441
442 ip6_flow_hdr(hdr, tclass, 0);
443
444 hdr->payload_len = htons(len);
445 hdr->nexthdr = IPPROTO_ICMPV6;
446 hdr->hop_limit = hop_limit;
447
448 hdr->saddr = *saddr;
449 hdr->daddr = *daddr;
450}
451
452static void ndisc_send_skb(struct sk_buff *skb,
453 const struct in6_addr *daddr,
454 const struct in6_addr *saddr)
455{
456 struct dst_entry *dst = skb_dst(skb);
457 struct net *net = dev_net(skb->dev);
458 struct sock *sk = net->ipv6.ndisc_sk;
459 struct inet6_dev *idev;
460 int err;
461 struct icmp6hdr *icmp6h = icmp6_hdr(skb);
462 u8 type;
463
464 type = icmp6h->icmp6_type;
465
466 if (!dst) {
467 struct flowi6 fl6;
468 int oif = skb->dev->ifindex;
469
470 icmpv6_flow_init(sk, &fl6, type, saddr, daddr, oif);
471 dst = icmp6_dst_alloc(skb->dev, &fl6);
472 if (IS_ERR(dst)) {
473 kfree_skb(skb);
474 return;
475 }
476
477 skb_dst_set(skb, dst);
478 }
479
480 icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, skb->len,
481 IPPROTO_ICMPV6,
482 csum_partial(icmp6h,
483 skb->len, 0));
484
485 ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, skb->len);
486
487 rcu_read_lock();
488 idev = __in6_dev_get(dst->dev);
489 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
490
491 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
492 net, sk, skb, NULL, dst->dev,
493 dst_output);
494 if (!err) {
495 ICMP6MSGOUT_INC_STATS(net, idev, type);
496 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
497 }
498
499 rcu_read_unlock();
500}
501
502void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr,
503 const struct in6_addr *solicited_addr,
504 bool router, bool solicited, bool override, bool inc_opt)
505{
506 struct sk_buff *skb;
507 struct in6_addr tmpaddr;
508 struct inet6_ifaddr *ifp;
509 const struct in6_addr *src_addr;
510 struct nd_msg *msg;
511 int optlen = 0;
512
513 /* for anycast or proxy, solicited_addr != src_addr */
514 ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1);
515 if (ifp) {
516 src_addr = solicited_addr;
517 if (ifp->flags & IFA_F_OPTIMISTIC)
518 override = false;
519 inc_opt |= ifp->idev->cnf.force_tllao;
520 in6_ifa_put(ifp);
521 } else {
522 if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr,
523 inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs,
524 &tmpaddr))
525 return;
526 src_addr = &tmpaddr;
527 }
528
529 if (!dev->addr_len)
530 inc_opt = false;
531 if (inc_opt)
532 optlen += ndisc_opt_addr_space(dev,
533 NDISC_NEIGHBOUR_ADVERTISEMENT);
534
535 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
536 if (!skb)
537 return;
538
539 msg = skb_put(skb, sizeof(*msg));
540 *msg = (struct nd_msg) {
541 .icmph = {
542 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
543 .icmp6_router = router,
544 .icmp6_solicited = solicited,
545 .icmp6_override = override,
546 },
547 .target = *solicited_addr,
548 };
549
550 if (inc_opt)
551 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR,
552 dev->dev_addr,
553 NDISC_NEIGHBOUR_ADVERTISEMENT);
554
555 ndisc_send_skb(skb, daddr, src_addr);
556}
557
558static void ndisc_send_unsol_na(struct net_device *dev)
559{
560 struct inet6_dev *idev;
561 struct inet6_ifaddr *ifa;
562
563 idev = in6_dev_get(dev);
564 if (!idev)
565 return;
566
567 read_lock_bh(&idev->lock);
568 list_for_each_entry(ifa, &idev->addr_list, if_list) {
569 /* skip tentative addresses until dad completes */
570 if (ifa->flags & IFA_F_TENTATIVE &&
571 !(ifa->flags & IFA_F_OPTIMISTIC))
572 continue;
573
574 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifa->addr,
575 /*router=*/ !!idev->cnf.forwarding,
576 /*solicited=*/ false, /*override=*/ true,
577 /*inc_opt=*/ true);
578 }
579 read_unlock_bh(&idev->lock);
580
581 in6_dev_put(idev);
582}
583
584void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit,
585 const struct in6_addr *daddr, const struct in6_addr *saddr,
586 u64 nonce)
587{
588 struct sk_buff *skb;
589 struct in6_addr addr_buf;
590 int inc_opt = dev->addr_len;
591 int optlen = 0;
592 struct nd_msg *msg;
593
594 if (!saddr) {
595 if (ipv6_get_lladdr(dev, &addr_buf,
596 (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
597 return;
598 saddr = &addr_buf;
599 }
600
601 if (ipv6_addr_any(saddr))
602 inc_opt = false;
603 if (inc_opt)
604 optlen += ndisc_opt_addr_space(dev,
605 NDISC_NEIGHBOUR_SOLICITATION);
606 if (nonce != 0)
607 optlen += 8;
608
609 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
610 if (!skb)
611 return;
612
613 msg = skb_put(skb, sizeof(*msg));
614 *msg = (struct nd_msg) {
615 .icmph = {
616 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
617 },
618 .target = *solicit,
619 };
620
621 if (inc_opt)
622 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
623 dev->dev_addr,
624 NDISC_NEIGHBOUR_SOLICITATION);
625 if (nonce != 0) {
626 u8 *opt = skb_put(skb, 8);
627
628 opt[0] = ND_OPT_NONCE;
629 opt[1] = 8 >> 3;
630 memcpy(opt + 2, &nonce, 6);
631 }
632
633 ndisc_send_skb(skb, daddr, saddr);
634}
635
636void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr,
637 const struct in6_addr *daddr)
638{
639 struct sk_buff *skb;
640 struct rs_msg *msg;
641 int send_sllao = dev->addr_len;
642 int optlen = 0;
643
644#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
645 /*
646 * According to section 2.2 of RFC 4429, we must not
647 * send router solicitations with a sllao from
648 * optimistic addresses, but we may send the solicitation
649 * if we don't include the sllao. So here we check
650 * if our address is optimistic, and if so, we
651 * suppress the inclusion of the sllao.
652 */
653 if (send_sllao) {
654 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr,
655 dev, 1);
656 if (ifp) {
657 if (ifp->flags & IFA_F_OPTIMISTIC) {
658 send_sllao = 0;
659 }
660 in6_ifa_put(ifp);
661 } else {
662 send_sllao = 0;
663 }
664 }
665#endif
666 if (send_sllao)
667 optlen += ndisc_opt_addr_space(dev, NDISC_ROUTER_SOLICITATION);
668
669 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
670 if (!skb)
671 return;
672
673 msg = skb_put(skb, sizeof(*msg));
674 *msg = (struct rs_msg) {
675 .icmph = {
676 .icmp6_type = NDISC_ROUTER_SOLICITATION,
677 },
678 };
679
680 if (send_sllao)
681 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
682 dev->dev_addr,
683 NDISC_ROUTER_SOLICITATION);
684
685 ndisc_send_skb(skb, daddr, saddr);
686}
687
688
689static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
690{
691 /*
692 * "The sender MUST return an ICMP
693 * destination unreachable"
694 */
695 dst_link_failure(skb);
696 kfree_skb(skb);
697}
698
699/* Called with locked neigh: either read or both */
700
701static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
702{
703 struct in6_addr *saddr = NULL;
704 struct in6_addr mcaddr;
705 struct net_device *dev = neigh->dev;
706 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
707 int probes = atomic_read(&neigh->probes);
708
709 if (skb && ipv6_chk_addr_and_flags(dev_net(dev), &ipv6_hdr(skb)->saddr,
710 dev, false, 1,
711 IFA_F_TENTATIVE|IFA_F_OPTIMISTIC))
712 saddr = &ipv6_hdr(skb)->saddr;
713 probes -= NEIGH_VAR(neigh->parms, UCAST_PROBES);
714 if (probes < 0) {
715 if (!(neigh->nud_state & NUD_VALID)) {
716 ND_PRINTK(1, dbg,
717 "%s: trying to ucast probe in NUD_INVALID: %pI6\n",
718 __func__, target);
719 }
720 ndisc_send_ns(dev, target, target, saddr, 0);
721 } else if ((probes -= NEIGH_VAR(neigh->parms, APP_PROBES)) < 0) {
722 neigh_app_ns(neigh);
723 } else {
724 addrconf_addr_solict_mult(target, &mcaddr);
725 ndisc_send_ns(dev, target, &mcaddr, saddr, 0);
726 }
727}
728
729static int pndisc_is_router(const void *pkey,
730 struct net_device *dev)
731{
732 struct pneigh_entry *n;
733 int ret = -1;
734
735 read_lock_bh(&nd_tbl.lock);
736 n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev);
737 if (n)
738 ret = !!(n->flags & NTF_ROUTER);
739 read_unlock_bh(&nd_tbl.lock);
740
741 return ret;
742}
743
744void ndisc_update(const struct net_device *dev, struct neighbour *neigh,
745 const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type,
746 struct ndisc_options *ndopts)
747{
748 neigh_update(neigh, lladdr, new, flags, 0);
749 /* report ndisc ops about neighbour update */
750 ndisc_ops_update(dev, neigh, flags, icmp6_type, ndopts);
751}
752
753static void ndisc_recv_ns(struct sk_buff *skb)
754{
755 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
756 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
757 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
758 u8 *lladdr = NULL;
759 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
760 offsetof(struct nd_msg, opt));
761 struct ndisc_options ndopts;
762 struct net_device *dev = skb->dev;
763 struct inet6_ifaddr *ifp;
764 struct inet6_dev *idev = NULL;
765 struct neighbour *neigh;
766 int dad = ipv6_addr_any(saddr);
767 bool inc;
768 int is_router = -1;
769 u64 nonce = 0;
770
771 if (skb->len < sizeof(struct nd_msg)) {
772 ND_PRINTK(2, warn, "NS: packet too short\n");
773 return;
774 }
775
776 if (ipv6_addr_is_multicast(&msg->target)) {
777 ND_PRINTK(2, warn, "NS: multicast target address\n");
778 return;
779 }
780
781 /*
782 * RFC2461 7.1.1:
783 * DAD has to be destined for solicited node multicast address.
784 */
785 if (dad && !ipv6_addr_is_solict_mult(daddr)) {
786 ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n");
787 return;
788 }
789
790 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) {
791 ND_PRINTK(2, warn, "NS: invalid ND options\n");
792 return;
793 }
794
795 if (ndopts.nd_opts_src_lladdr) {
796 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
797 if (!lladdr) {
798 ND_PRINTK(2, warn,
799 "NS: invalid link-layer address length\n");
800 return;
801 }
802
803 /* RFC2461 7.1.1:
804 * If the IP source address is the unspecified address,
805 * there MUST NOT be source link-layer address option
806 * in the message.
807 */
808 if (dad) {
809 ND_PRINTK(2, warn,
810 "NS: bad DAD packet (link-layer address option)\n");
811 return;
812 }
813 }
814 if (ndopts.nd_opts_nonce)
815 memcpy(&nonce, (u8 *)(ndopts.nd_opts_nonce + 1), 6);
816
817 inc = ipv6_addr_is_multicast(daddr);
818
819 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
820 if (ifp) {
821have_ifp:
822 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
823 if (dad) {
824 if (nonce != 0 && ifp->dad_nonce == nonce) {
825 u8 *np = (u8 *)&nonce;
826 /* Matching nonce if looped back */
827 ND_PRINTK(2, notice,
828 "%s: IPv6 DAD loopback for address %pI6c nonce %pM ignored\n",
829 ifp->idev->dev->name,
830 &ifp->addr, np);
831 goto out;
832 }
833 /*
834 * We are colliding with another node
835 * who is doing DAD
836 * so fail our DAD process
837 */
838 addrconf_dad_failure(skb, ifp);
839 return;
840 } else {
841 /*
842 * This is not a dad solicitation.
843 * If we are an optimistic node,
844 * we should respond.
845 * Otherwise, we should ignore it.
846 */
847 if (!(ifp->flags & IFA_F_OPTIMISTIC))
848 goto out;
849 }
850 }
851
852 idev = ifp->idev;
853 } else {
854 struct net *net = dev_net(dev);
855
856 /* perhaps an address on the master device */
857 if (netif_is_l3_slave(dev)) {
858 struct net_device *mdev;
859
860 mdev = netdev_master_upper_dev_get_rcu(dev);
861 if (mdev) {
862 ifp = ipv6_get_ifaddr(net, &msg->target, mdev, 1);
863 if (ifp)
864 goto have_ifp;
865 }
866 }
867
868 idev = in6_dev_get(dev);
869 if (!idev) {
870 /* XXX: count this drop? */
871 return;
872 }
873
874 if (ipv6_chk_acast_addr(net, dev, &msg->target) ||
875 (idev->cnf.forwarding &&
876 (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) &&
877 (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) {
878 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
879 skb->pkt_type != PACKET_HOST &&
880 inc &&
881 NEIGH_VAR(idev->nd_parms, PROXY_DELAY) != 0) {
882 /*
883 * for anycast or proxy,
884 * sender should delay its response
885 * by a random time between 0 and
886 * MAX_ANYCAST_DELAY_TIME seconds.
887 * (RFC2461) -- yoshfuji
888 */
889 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
890 if (n)
891 pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
892 goto out;
893 }
894 } else
895 goto out;
896 }
897
898 if (is_router < 0)
899 is_router = idev->cnf.forwarding;
900
901 if (dad) {
902 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &msg->target,
903 !!is_router, false, (ifp != NULL), true);
904 goto out;
905 }
906
907 if (inc)
908 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
909 else
910 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
911
912 /*
913 * update / create cache entry
914 * for the source address
915 */
916 neigh = __neigh_lookup(&nd_tbl, saddr, dev,
917 !inc || lladdr || !dev->addr_len);
918 if (neigh)
919 ndisc_update(dev, neigh, lladdr, NUD_STALE,
920 NEIGH_UPDATE_F_WEAK_OVERRIDE|
921 NEIGH_UPDATE_F_OVERRIDE,
922 NDISC_NEIGHBOUR_SOLICITATION, &ndopts);
923 if (neigh || !dev->header_ops) {
924 ndisc_send_na(dev, saddr, &msg->target, !!is_router,
925 true, (ifp != NULL && inc), inc);
926 if (neigh)
927 neigh_release(neigh);
928 }
929
930out:
931 if (ifp)
932 in6_ifa_put(ifp);
933 else
934 in6_dev_put(idev);
935}
936
937static void ndisc_recv_na(struct sk_buff *skb)
938{
939 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
940 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
941 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
942 u8 *lladdr = NULL;
943 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
944 offsetof(struct nd_msg, opt));
945 struct ndisc_options ndopts;
946 struct net_device *dev = skb->dev;
947 struct inet6_dev *idev = __in6_dev_get(dev);
948 struct inet6_ifaddr *ifp;
949 struct neighbour *neigh;
950
951 if (skb->len < sizeof(struct nd_msg)) {
952 ND_PRINTK(2, warn, "NA: packet too short\n");
953 return;
954 }
955
956 if (ipv6_addr_is_multicast(&msg->target)) {
957 ND_PRINTK(2, warn, "NA: target address is multicast\n");
958 return;
959 }
960
961 if (ipv6_addr_is_multicast(daddr) &&
962 msg->icmph.icmp6_solicited) {
963 ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n");
964 return;
965 }
966
967 /* For some 802.11 wireless deployments (and possibly other networks),
968 * there will be a NA proxy and unsolicitd packets are attacks
969 * and thus should not be accepted.
970 */
971 if (!msg->icmph.icmp6_solicited && idev &&
972 idev->cnf.drop_unsolicited_na)
973 return;
974
975 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) {
976 ND_PRINTK(2, warn, "NS: invalid ND option\n");
977 return;
978 }
979 if (ndopts.nd_opts_tgt_lladdr) {
980 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
981 if (!lladdr) {
982 ND_PRINTK(2, warn,
983 "NA: invalid link-layer address length\n");
984 return;
985 }
986 }
987 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
988 if (ifp) {
989 if (skb->pkt_type != PACKET_LOOPBACK
990 && (ifp->flags & IFA_F_TENTATIVE)) {
991 addrconf_dad_failure(skb, ifp);
992 return;
993 }
994 /* What should we make now? The advertisement
995 is invalid, but ndisc specs say nothing
996 about it. It could be misconfiguration, or
997 an smart proxy agent tries to help us :-)
998
999 We should not print the error if NA has been
1000 received from loopback - it is just our own
1001 unsolicited advertisement.
1002 */
1003 if (skb->pkt_type != PACKET_LOOPBACK)
1004 ND_PRINTK(1, warn,
1005 "NA: %pM advertised our address %pI6c on %s!\n",
1006 eth_hdr(skb)->h_source, &ifp->addr, ifp->idev->dev->name);
1007 in6_ifa_put(ifp);
1008 return;
1009 }
1010 neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
1011
1012 if (neigh) {
1013 u8 old_flags = neigh->flags;
1014 struct net *net = dev_net(dev);
1015
1016 if (neigh->nud_state & NUD_FAILED)
1017 goto out;
1018
1019 /*
1020 * Don't update the neighbor cache entry on a proxy NA from
1021 * ourselves because either the proxied node is off link or it
1022 * has already sent a NA to us.
1023 */
1024 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
1025 net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp &&
1026 pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) {
1027 /* XXX: idev->cnf.proxy_ndp */
1028 goto out;
1029 }
1030
1031 ndisc_update(dev, neigh, lladdr,
1032 msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
1033 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1034 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
1035 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1036 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0),
1037 NDISC_NEIGHBOUR_ADVERTISEMENT, &ndopts);
1038
1039 if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
1040 /*
1041 * Change: router to host
1042 */
1043 rt6_clean_tohost(dev_net(dev), saddr);
1044 }
1045
1046out:
1047 neigh_release(neigh);
1048 }
1049}
1050
1051static void ndisc_recv_rs(struct sk_buff *skb)
1052{
1053 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
1054 unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
1055 struct neighbour *neigh;
1056 struct inet6_dev *idev;
1057 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
1058 struct ndisc_options ndopts;
1059 u8 *lladdr = NULL;
1060
1061 if (skb->len < sizeof(*rs_msg))
1062 return;
1063
1064 idev = __in6_dev_get(skb->dev);
1065 if (!idev) {
1066 ND_PRINTK(1, err, "RS: can't find in6 device\n");
1067 return;
1068 }
1069
1070 /* Don't accept RS if we're not in router mode */
1071 if (!idev->cnf.forwarding)
1072 goto out;
1073
1074 /*
1075 * Don't update NCE if src = ::;
1076 * this implies that the source node has no ip address assigned yet.
1077 */
1078 if (ipv6_addr_any(saddr))
1079 goto out;
1080
1081 /* Parse ND options */
1082 if (!ndisc_parse_options(skb->dev, rs_msg->opt, ndoptlen, &ndopts)) {
1083 ND_PRINTK(2, notice, "NS: invalid ND option, ignored\n");
1084 goto out;
1085 }
1086
1087 if (ndopts.nd_opts_src_lladdr) {
1088 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1089 skb->dev);
1090 if (!lladdr)
1091 goto out;
1092 }
1093
1094 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
1095 if (neigh) {
1096 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
1097 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1098 NEIGH_UPDATE_F_OVERRIDE|
1099 NEIGH_UPDATE_F_OVERRIDE_ISROUTER,
1100 NDISC_ROUTER_SOLICITATION, &ndopts);
1101 neigh_release(neigh);
1102 }
1103out:
1104 return;
1105}
1106
1107static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
1108{
1109 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
1110 struct sk_buff *skb;
1111 struct nlmsghdr *nlh;
1112 struct nduseroptmsg *ndmsg;
1113 struct net *net = dev_net(ra->dev);
1114 int err;
1115 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
1116 + (opt->nd_opt_len << 3));
1117 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
1118
1119 skb = nlmsg_new(msg_size, GFP_ATOMIC);
1120 if (!skb) {
1121 err = -ENOBUFS;
1122 goto errout;
1123 }
1124
1125 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
1126 if (!nlh) {
1127 goto nla_put_failure;
1128 }
1129
1130 ndmsg = nlmsg_data(nlh);
1131 ndmsg->nduseropt_family = AF_INET6;
1132 ndmsg->nduseropt_ifindex = ra->dev->ifindex;
1133 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
1134 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
1135 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
1136
1137 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
1138
1139 if (nla_put_in6_addr(skb, NDUSEROPT_SRCADDR, &ipv6_hdr(ra)->saddr))
1140 goto nla_put_failure;
1141 nlmsg_end(skb, nlh);
1142
1143 rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC);
1144 return;
1145
1146nla_put_failure:
1147 nlmsg_free(skb);
1148 err = -EMSGSIZE;
1149errout:
1150 rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err);
1151}
1152
1153static void ndisc_router_discovery(struct sk_buff *skb)
1154{
1155 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
1156 struct neighbour *neigh = NULL;
1157 struct inet6_dev *in6_dev;
1158 struct rt6_info *rt = NULL;
1159 int lifetime;
1160 struct ndisc_options ndopts;
1161 int optlen;
1162 unsigned int pref = 0;
1163 __u32 old_if_flags;
1164 bool send_ifinfo_notify = false;
1165
1166 __u8 *opt = (__u8 *)(ra_msg + 1);
1167
1168 optlen = (skb_tail_pointer(skb) - skb_transport_header(skb)) -
1169 sizeof(struct ra_msg);
1170
1171 ND_PRINTK(2, info,
1172 "RA: %s, dev: %s\n",
1173 __func__, skb->dev->name);
1174 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1175 ND_PRINTK(2, warn, "RA: source address is not link-local\n");
1176 return;
1177 }
1178 if (optlen < 0) {
1179 ND_PRINTK(2, warn, "RA: packet too short\n");
1180 return;
1181 }
1182
1183#ifdef CONFIG_IPV6_NDISC_NODETYPE
1184 if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) {
1185 ND_PRINTK(2, warn, "RA: from host or unauthorized router\n");
1186 return;
1187 }
1188#endif
1189
1190 /*
1191 * set the RA_RECV flag in the interface
1192 */
1193
1194 in6_dev = __in6_dev_get(skb->dev);
1195 if (!in6_dev) {
1196 ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n",
1197 skb->dev->name);
1198 return;
1199 }
1200
1201 if (!ndisc_parse_options(skb->dev, opt, optlen, &ndopts)) {
1202 ND_PRINTK(2, warn, "RA: invalid ND options\n");
1203 return;
1204 }
1205
1206 if (!ipv6_accept_ra(in6_dev)) {
1207 ND_PRINTK(2, info,
1208 "RA: %s, did not accept ra for dev: %s\n",
1209 __func__, skb->dev->name);
1210 goto skip_linkparms;
1211 }
1212
1213#ifdef CONFIG_IPV6_NDISC_NODETYPE
1214 /* skip link-specific parameters from interior routers */
1215 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) {
1216 ND_PRINTK(2, info,
1217 "RA: %s, nodetype is NODEFAULT, dev: %s\n",
1218 __func__, skb->dev->name);
1219 goto skip_linkparms;
1220 }
1221#endif
1222
1223 if (in6_dev->if_flags & IF_RS_SENT) {
1224 /*
1225 * flag that an RA was received after an RS was sent
1226 * out on this interface.
1227 */
1228 in6_dev->if_flags |= IF_RA_RCVD;
1229 }
1230
1231 /*
1232 * Remember the managed/otherconf flags from most recently
1233 * received RA message (RFC 2462) -- yoshfuji
1234 */
1235 old_if_flags = in6_dev->if_flags;
1236 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1237 IF_RA_OTHERCONF)) |
1238 (ra_msg->icmph.icmp6_addrconf_managed ?
1239 IF_RA_MANAGED : 0) |
1240 (ra_msg->icmph.icmp6_addrconf_other ?
1241 IF_RA_OTHERCONF : 0);
1242
1243 if (old_if_flags != in6_dev->if_flags)
1244 send_ifinfo_notify = true;
1245
1246 if (!in6_dev->cnf.accept_ra_defrtr) {
1247 ND_PRINTK(2, info,
1248 "RA: %s, defrtr is false for dev: %s\n",
1249 __func__, skb->dev->name);
1250 goto skip_defrtr;
1251 }
1252
1253 /* Do not accept RA with source-addr found on local machine unless
1254 * accept_ra_from_local is set to true.
1255 */
1256 if (!in6_dev->cnf.accept_ra_from_local &&
1257 ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr,
1258 in6_dev->dev, 0)) {
1259 ND_PRINTK(2, info,
1260 "RA from local address detected on dev: %s: default router ignored\n",
1261 skb->dev->name);
1262 goto skip_defrtr;
1263 }
1264
1265 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1266
1267#ifdef CONFIG_IPV6_ROUTER_PREF
1268 pref = ra_msg->icmph.icmp6_router_pref;
1269 /* 10b is handled as if it were 00b (medium) */
1270 if (pref == ICMPV6_ROUTER_PREF_INVALID ||
1271 !in6_dev->cnf.accept_ra_rtr_pref)
1272 pref = ICMPV6_ROUTER_PREF_MEDIUM;
1273#endif
1274
1275 rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev);
1276
1277 if (rt) {
1278 neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr);
1279 if (!neigh) {
1280 ND_PRINTK(0, err,
1281 "RA: %s got default router without neighbour\n",
1282 __func__);
1283 ip6_rt_put(rt);
1284 return;
1285 }
1286 }
1287 if (rt && lifetime == 0) {
1288 ip6_del_rt(rt);
1289 rt = NULL;
1290 }
1291
1292 ND_PRINTK(3, info, "RA: rt: %p lifetime: %d, for dev: %s\n",
1293 rt, lifetime, skb->dev->name);
1294 if (!rt && lifetime) {
1295 ND_PRINTK(3, info, "RA: adding default router\n");
1296
1297 rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref);
1298 if (!rt) {
1299 ND_PRINTK(0, err,
1300 "RA: %s failed to add default route\n",
1301 __func__);
1302 return;
1303 }
1304
1305 neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr);
1306 if (!neigh) {
1307 ND_PRINTK(0, err,
1308 "RA: %s got default router without neighbour\n",
1309 __func__);
1310 ip6_rt_put(rt);
1311 return;
1312 }
1313 neigh->flags |= NTF_ROUTER;
1314 } else if (rt) {
1315 rt->rt6i_flags = (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
1316 }
1317
1318 if (rt)
1319 rt6_set_expires(rt, jiffies + (HZ * lifetime));
1320 if (in6_dev->cnf.accept_ra_min_hop_limit < 256 &&
1321 ra_msg->icmph.icmp6_hop_limit) {
1322 if (in6_dev->cnf.accept_ra_min_hop_limit <= ra_msg->icmph.icmp6_hop_limit) {
1323 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
1324 if (rt)
1325 dst_metric_set(&rt->dst, RTAX_HOPLIMIT,
1326 ra_msg->icmph.icmp6_hop_limit);
1327 } else {
1328 ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than minimum\n");
1329 }
1330 }
1331
1332skip_defrtr:
1333
1334 /*
1335 * Update Reachable Time and Retrans Timer
1336 */
1337
1338 if (in6_dev->nd_parms) {
1339 unsigned long rtime = ntohl(ra_msg->retrans_timer);
1340
1341 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1342 rtime = (rtime*HZ)/1000;
1343 if (rtime < HZ/10)
1344 rtime = HZ/10;
1345 NEIGH_VAR_SET(in6_dev->nd_parms, RETRANS_TIME, rtime);
1346 in6_dev->tstamp = jiffies;
1347 send_ifinfo_notify = true;
1348 }
1349
1350 rtime = ntohl(ra_msg->reachable_time);
1351 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1352 rtime = (rtime*HZ)/1000;
1353
1354 if (rtime < HZ/10)
1355 rtime = HZ/10;
1356
1357 if (rtime != NEIGH_VAR(in6_dev->nd_parms, BASE_REACHABLE_TIME)) {
1358 NEIGH_VAR_SET(in6_dev->nd_parms,
1359 BASE_REACHABLE_TIME, rtime);
1360 NEIGH_VAR_SET(in6_dev->nd_parms,
1361 GC_STALETIME, 3 * rtime);
1362 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1363 in6_dev->tstamp = jiffies;
1364 send_ifinfo_notify = true;
1365 }
1366 }
1367 }
1368
1369 /*
1370 * Send a notify if RA changed managed/otherconf flags or timer settings
1371 */
1372 if (send_ifinfo_notify)
1373 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1374
1375skip_linkparms:
1376
1377 /*
1378 * Process options.
1379 */
1380
1381 if (!neigh)
1382 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
1383 skb->dev, 1);
1384 if (neigh) {
1385 u8 *lladdr = NULL;
1386 if (ndopts.nd_opts_src_lladdr) {
1387 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1388 skb->dev);
1389 if (!lladdr) {
1390 ND_PRINTK(2, warn,
1391 "RA: invalid link-layer address length\n");
1392 goto out;
1393 }
1394 }
1395 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
1396 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1397 NEIGH_UPDATE_F_OVERRIDE|
1398 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1399 NEIGH_UPDATE_F_ISROUTER,
1400 NDISC_ROUTER_ADVERTISEMENT, &ndopts);
1401 }
1402
1403 if (!ipv6_accept_ra(in6_dev)) {
1404 ND_PRINTK(2, info,
1405 "RA: %s, accept_ra is false for dev: %s\n",
1406 __func__, skb->dev->name);
1407 goto out;
1408 }
1409
1410#ifdef CONFIG_IPV6_ROUTE_INFO
1411 if (!in6_dev->cnf.accept_ra_from_local &&
1412 ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr,
1413 in6_dev->dev, 0)) {
1414 ND_PRINTK(2, info,
1415 "RA from local address detected on dev: %s: router info ignored.\n",
1416 skb->dev->name);
1417 goto skip_routeinfo;
1418 }
1419
1420 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
1421 struct nd_opt_hdr *p;
1422 for (p = ndopts.nd_opts_ri;
1423 p;
1424 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
1425 struct route_info *ri = (struct route_info *)p;
1426#ifdef CONFIG_IPV6_NDISC_NODETYPE
1427 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT &&
1428 ri->prefix_len == 0)
1429 continue;
1430#endif
1431 if (ri->prefix_len == 0 &&
1432 !in6_dev->cnf.accept_ra_defrtr)
1433 continue;
1434 if (ri->prefix_len < in6_dev->cnf.accept_ra_rt_info_min_plen)
1435 continue;
1436 if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
1437 continue;
1438 rt6_route_rcv(skb->dev, (u8 *)p, (p->nd_opt_len) << 3,
1439 &ipv6_hdr(skb)->saddr);
1440 }
1441 }
1442
1443skip_routeinfo:
1444#endif
1445
1446#ifdef CONFIG_IPV6_NDISC_NODETYPE
1447 /* skip link-specific ndopts from interior routers */
1448 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) {
1449 ND_PRINTK(2, info,
1450 "RA: %s, nodetype is NODEFAULT (interior routes), dev: %s\n",
1451 __func__, skb->dev->name);
1452 goto out;
1453 }
1454#endif
1455
1456 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
1457 struct nd_opt_hdr *p;
1458 for (p = ndopts.nd_opts_pi;
1459 p;
1460 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1461 addrconf_prefix_rcv(skb->dev, (u8 *)p,
1462 (p->nd_opt_len) << 3,
1463 ndopts.nd_opts_src_lladdr != NULL);
1464 }
1465 }
1466
1467 if (ndopts.nd_opts_mtu && in6_dev->cnf.accept_ra_mtu) {
1468 __be32 n;
1469 u32 mtu;
1470
1471 memcpy(&n, ((u8 *)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1472 mtu = ntohl(n);
1473
1474 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1475 ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu);
1476 } else if (in6_dev->cnf.mtu6 != mtu) {
1477 in6_dev->cnf.mtu6 = mtu;
1478
1479 if (rt)
1480 dst_metric_set(&rt->dst, RTAX_MTU, mtu);
1481
1482 rt6_mtu_change(skb->dev, mtu);
1483 }
1484 }
1485
1486 if (ndopts.nd_useropts) {
1487 struct nd_opt_hdr *p;
1488 for (p = ndopts.nd_useropts;
1489 p;
1490 p = ndisc_next_useropt(skb->dev, p,
1491 ndopts.nd_useropts_end)) {
1492 ndisc_ra_useropt(skb, p);
1493 }
1494 }
1495
1496 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1497 ND_PRINTK(2, warn, "RA: invalid RA options\n");
1498 }
1499out:
1500 ip6_rt_put(rt);
1501 if (neigh)
1502 neigh_release(neigh);
1503}
1504
1505static void ndisc_redirect_rcv(struct sk_buff *skb)
1506{
1507 u8 *hdr;
1508 struct ndisc_options ndopts;
1509 struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb);
1510 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
1511 offsetof(struct rd_msg, opt));
1512
1513#ifdef CONFIG_IPV6_NDISC_NODETYPE
1514 switch (skb->ndisc_nodetype) {
1515 case NDISC_NODETYPE_HOST:
1516 case NDISC_NODETYPE_NODEFAULT:
1517 ND_PRINTK(2, warn,
1518 "Redirect: from host or unauthorized router\n");
1519 return;
1520 }
1521#endif
1522
1523 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1524 ND_PRINTK(2, warn,
1525 "Redirect: source address is not link-local\n");
1526 return;
1527 }
1528
1529 if (!ndisc_parse_options(skb->dev, msg->opt, ndoptlen, &ndopts))
1530 return;
1531
1532 if (!ndopts.nd_opts_rh) {
1533 ip6_redirect_no_header(skb, dev_net(skb->dev),
1534 skb->dev->ifindex, 0);
1535 return;
1536 }
1537
1538 hdr = (u8 *)ndopts.nd_opts_rh;
1539 hdr += 8;
1540 if (!pskb_pull(skb, hdr - skb_transport_header(skb)))
1541 return;
1542
1543 icmpv6_notify(skb, NDISC_REDIRECT, 0, 0);
1544}
1545
1546static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb,
1547 struct sk_buff *orig_skb,
1548 int rd_len)
1549{
1550 u8 *opt = skb_put(skb, rd_len);
1551
1552 memset(opt, 0, 8);
1553 *(opt++) = ND_OPT_REDIRECT_HDR;
1554 *(opt++) = (rd_len >> 3);
1555 opt += 6;
1556
1557 skb_copy_bits(orig_skb, skb_network_offset(orig_skb), opt,
1558 rd_len - 8);
1559}
1560
1561void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
1562{
1563 struct net_device *dev = skb->dev;
1564 struct net *net = dev_net(dev);
1565 struct sock *sk = net->ipv6.ndisc_sk;
1566 int optlen = 0;
1567 struct inet_peer *peer;
1568 struct sk_buff *buff;
1569 struct rd_msg *msg;
1570 struct in6_addr saddr_buf;
1571 struct rt6_info *rt;
1572 struct dst_entry *dst;
1573 struct flowi6 fl6;
1574 int rd_len;
1575 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL,
1576 ops_data_buf[NDISC_OPS_REDIRECT_DATA_SPACE], *ops_data = NULL;
1577 bool ret;
1578
1579 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
1580 ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n",
1581 dev->name);
1582 return;
1583 }
1584
1585 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
1586 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1587 ND_PRINTK(2, warn,
1588 "Redirect: target address is not link-local unicast\n");
1589 return;
1590 }
1591
1592 icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT,
1593 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex);
1594
1595 dst = ip6_route_output(net, NULL, &fl6);
1596 if (dst->error) {
1597 dst_release(dst);
1598 return;
1599 }
1600 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
1601 if (IS_ERR(dst))
1602 return;
1603
1604 rt = (struct rt6_info *) dst;
1605
1606 if (rt->rt6i_flags & RTF_GATEWAY) {
1607 ND_PRINTK(2, warn,
1608 "Redirect: destination is not a neighbour\n");
1609 goto release;
1610 }
1611 peer = inet_getpeer_v6(net->ipv6.peers, &ipv6_hdr(skb)->saddr, 1);
1612 ret = inet_peer_xrlim_allow(peer, 1*HZ);
1613 if (peer)
1614 inet_putpeer(peer);
1615 if (!ret)
1616 goto release;
1617
1618 if (dev->addr_len) {
1619 struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target);
1620 if (!neigh) {
1621 ND_PRINTK(2, warn,
1622 "Redirect: no neigh for target address\n");
1623 goto release;
1624 }
1625
1626 read_lock_bh(&neigh->lock);
1627 if (neigh->nud_state & NUD_VALID) {
1628 memcpy(ha_buf, neigh->ha, dev->addr_len);
1629 read_unlock_bh(&neigh->lock);
1630 ha = ha_buf;
1631 optlen += ndisc_redirect_opt_addr_space(dev, neigh,
1632 ops_data_buf,
1633 &ops_data);
1634 } else
1635 read_unlock_bh(&neigh->lock);
1636
1637 neigh_release(neigh);
1638 }
1639
1640 rd_len = min_t(unsigned int,
1641 IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen,
1642 skb->len + 8);
1643 rd_len &= ~0x7;
1644 optlen += rd_len;
1645
1646 buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
1647 if (!buff)
1648 goto release;
1649
1650 msg = skb_put(buff, sizeof(*msg));
1651 *msg = (struct rd_msg) {
1652 .icmph = {
1653 .icmp6_type = NDISC_REDIRECT,
1654 },
1655 .target = *target,
1656 .dest = ipv6_hdr(skb)->daddr,
1657 };
1658
1659 /*
1660 * include target_address option
1661 */
1662
1663 if (ha)
1664 ndisc_fill_redirect_addr_option(buff, ha, ops_data);
1665
1666 /*
1667 * build redirect option and copy skb over to the new packet.
1668 */
1669
1670 if (rd_len)
1671 ndisc_fill_redirect_hdr_option(buff, skb, rd_len);
1672
1673 skb_dst_set(buff, dst);
1674 ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf);
1675 return;
1676
1677release:
1678 dst_release(dst);
1679}
1680
1681static void pndisc_redo(struct sk_buff *skb)
1682{
1683 ndisc_recv_ns(skb);
1684 kfree_skb(skb);
1685}
1686
1687static bool ndisc_suppress_frag_ndisc(struct sk_buff *skb)
1688{
1689 struct inet6_dev *idev = __in6_dev_get(skb->dev);
1690
1691 if (!idev)
1692 return true;
1693 if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED &&
1694 idev->cnf.suppress_frag_ndisc) {
1695 net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n");
1696 return true;
1697 }
1698 return false;
1699}
1700
1701int ndisc_rcv(struct sk_buff *skb)
1702{
1703 struct nd_msg *msg;
1704
1705 if (ndisc_suppress_frag_ndisc(skb))
1706 return 0;
1707
1708 if (skb_linearize(skb))
1709 return 0;
1710
1711 msg = (struct nd_msg *)skb_transport_header(skb);
1712
1713 __skb_push(skb, skb->data - skb_transport_header(skb));
1714
1715 if (ipv6_hdr(skb)->hop_limit != 255) {
1716 ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n",
1717 ipv6_hdr(skb)->hop_limit);
1718 return 0;
1719 }
1720
1721 if (msg->icmph.icmp6_code != 0) {
1722 ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n",
1723 msg->icmph.icmp6_code);
1724 return 0;
1725 }
1726
1727 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1728
1729 switch (msg->icmph.icmp6_type) {
1730 case NDISC_NEIGHBOUR_SOLICITATION:
1731 ndisc_recv_ns(skb);
1732 break;
1733
1734 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1735 ndisc_recv_na(skb);
1736 break;
1737
1738 case NDISC_ROUTER_SOLICITATION:
1739 ndisc_recv_rs(skb);
1740 break;
1741
1742 case NDISC_ROUTER_ADVERTISEMENT:
1743 ndisc_router_discovery(skb);
1744 break;
1745
1746 case NDISC_REDIRECT:
1747 ndisc_redirect_rcv(skb);
1748 break;
1749 }
1750
1751 return 0;
1752}
1753
1754static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1755{
1756 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1757 struct netdev_notifier_change_info *change_info;
1758 struct net *net = dev_net(dev);
1759 struct inet6_dev *idev;
1760
1761 switch (event) {
1762 case NETDEV_CHANGEADDR:
1763 neigh_changeaddr(&nd_tbl, dev);
1764 fib6_run_gc(0, net, false);
1765 /* fallthrough */
1766 case NETDEV_UP:
1767 idev = in6_dev_get(dev);
1768 if (!idev)
1769 break;
1770 if (idev->cnf.ndisc_notify ||
1771 net->ipv6.devconf_all->ndisc_notify)
1772 ndisc_send_unsol_na(dev);
1773 in6_dev_put(idev);
1774 break;
1775 case NETDEV_CHANGE:
1776 change_info = ptr;
1777 if (change_info->flags_changed & IFF_NOARP)
1778 neigh_changeaddr(&nd_tbl, dev);
1779 break;
1780 case NETDEV_DOWN:
1781 neigh_ifdown(&nd_tbl, dev);
1782 fib6_run_gc(0, net, false);
1783 break;
1784 case NETDEV_NOTIFY_PEERS:
1785 ndisc_send_unsol_na(dev);
1786 break;
1787 default:
1788 break;
1789 }
1790
1791 return NOTIFY_DONE;
1792}
1793
1794static struct notifier_block ndisc_netdev_notifier = {
1795 .notifier_call = ndisc_netdev_event,
1796 .priority = ADDRCONF_NOTIFY_PRIORITY - 5,
1797};
1798
1799#ifdef CONFIG_SYSCTL
1800static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
1801 const char *func, const char *dev_name)
1802{
1803 static char warncomm[TASK_COMM_LEN];
1804 static int warned;
1805 if (strcmp(warncomm, current->comm) && warned < 5) {
1806 strcpy(warncomm, current->comm);
1807 pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n",
1808 warncomm, func,
1809 dev_name, ctl->procname,
1810 dev_name, ctl->procname);
1811 warned++;
1812 }
1813}
1814
1815int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void __user *buffer, size_t *lenp, loff_t *ppos)
1816{
1817 struct net_device *dev = ctl->extra1;
1818 struct inet6_dev *idev;
1819 int ret;
1820
1821 if ((strcmp(ctl->procname, "retrans_time") == 0) ||
1822 (strcmp(ctl->procname, "base_reachable_time") == 0))
1823 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1824
1825 if (strcmp(ctl->procname, "retrans_time") == 0)
1826 ret = neigh_proc_dointvec(ctl, write, buffer, lenp, ppos);
1827
1828 else if (strcmp(ctl->procname, "base_reachable_time") == 0)
1829 ret = neigh_proc_dointvec_jiffies(ctl, write,
1830 buffer, lenp, ppos);
1831
1832 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
1833 (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
1834 ret = neigh_proc_dointvec_ms_jiffies(ctl, write,
1835 buffer, lenp, ppos);
1836 else
1837 ret = -1;
1838
1839 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1840 if (ctl->data == &NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME))
1841 idev->nd_parms->reachable_time =
1842 neigh_rand_reach_time(NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME));
1843 idev->tstamp = jiffies;
1844 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1845 in6_dev_put(idev);
1846 }
1847 return ret;
1848}
1849
1850
1851#endif
1852
1853static int __net_init ndisc_net_init(struct net *net)
1854{
1855 struct ipv6_pinfo *np;
1856 struct sock *sk;
1857 int err;
1858
1859 err = inet_ctl_sock_create(&sk, PF_INET6,
1860 SOCK_RAW, IPPROTO_ICMPV6, net);
1861 if (err < 0) {
1862 ND_PRINTK(0, err,
1863 "NDISC: Failed to initialize the control socket (err %d)\n",
1864 err);
1865 return err;
1866 }
1867
1868 net->ipv6.ndisc_sk = sk;
1869
1870 np = inet6_sk(sk);
1871 np->hop_limit = 255;
1872 /* Do not loopback ndisc messages */
1873 np->mc_loop = 0;
1874
1875 return 0;
1876}
1877
1878static void __net_exit ndisc_net_exit(struct net *net)
1879{
1880 inet_ctl_sock_destroy(net->ipv6.ndisc_sk);
1881}
1882
1883static struct pernet_operations ndisc_net_ops = {
1884 .init = ndisc_net_init,
1885 .exit = ndisc_net_exit,
1886};
1887
1888int __init ndisc_init(void)
1889{
1890 int err;
1891
1892 err = register_pernet_subsys(&ndisc_net_ops);
1893 if (err)
1894 return err;
1895 /*
1896 * Initialize the neighbour table
1897 */
1898 neigh_table_init(NEIGH_ND_TABLE, &nd_tbl);
1899
1900#ifdef CONFIG_SYSCTL
1901 err = neigh_sysctl_register(NULL, &nd_tbl.parms,
1902 ndisc_ifinfo_sysctl_change);
1903 if (err)
1904 goto out_unregister_pernet;
1905out:
1906#endif
1907 return err;
1908
1909#ifdef CONFIG_SYSCTL
1910out_unregister_pernet:
1911 unregister_pernet_subsys(&ndisc_net_ops);
1912 goto out;
1913#endif
1914}
1915
1916int __init ndisc_late_init(void)
1917{
1918 return register_netdevice_notifier(&ndisc_netdev_notifier);
1919}
1920
1921void ndisc_late_cleanup(void)
1922{
1923 unregister_netdevice_notifier(&ndisc_netdev_notifier);
1924}
1925
1926void ndisc_cleanup(void)
1927{
1928#ifdef CONFIG_SYSCTL
1929 neigh_sysctl_unregister(&nd_tbl.parms);
1930#endif
1931 neigh_table_clear(NEIGH_ND_TABLE, &nd_tbl);
1932 unregister_pernet_subsys(&ndisc_net_ops);
1933}
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_RDNSS ||
201 opt->nd_opt_type == ND_OPT_DNSSL ||
202 opt->nd_opt_type == ND_OPT_CAPTIVE_PORTAL ||
203 opt->nd_opt_type == ND_OPT_PREF64 ||
204 ndisc_ops_is_useropt(dev, opt->nd_opt_type);
205}
206
207static struct nd_opt_hdr *ndisc_next_useropt(const struct net_device *dev,
208 struct nd_opt_hdr *cur,
209 struct nd_opt_hdr *end)
210{
211 if (!cur || !end || cur >= end)
212 return NULL;
213 do {
214 cur = ((void *)cur) + (cur->nd_opt_len << 3);
215 } while (cur < end && !ndisc_is_useropt(dev, cur));
216 return cur <= end && ndisc_is_useropt(dev, cur) ? cur : NULL;
217}
218
219struct ndisc_options *ndisc_parse_options(const struct net_device *dev,
220 u8 *opt, int opt_len,
221 struct ndisc_options *ndopts)
222{
223 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
224
225 if (!nd_opt || opt_len < 0 || !ndopts)
226 return NULL;
227 memset(ndopts, 0, sizeof(*ndopts));
228 while (opt_len) {
229 int l;
230 if (opt_len < sizeof(struct nd_opt_hdr))
231 return NULL;
232 l = nd_opt->nd_opt_len << 3;
233 if (opt_len < l || l == 0)
234 return NULL;
235 if (ndisc_ops_parse_options(dev, nd_opt, ndopts))
236 goto next_opt;
237 switch (nd_opt->nd_opt_type) {
238 case ND_OPT_SOURCE_LL_ADDR:
239 case ND_OPT_TARGET_LL_ADDR:
240 case ND_OPT_MTU:
241 case ND_OPT_NONCE:
242 case ND_OPT_REDIRECT_HDR:
243 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
244 ND_PRINTK(2, warn,
245 "%s: duplicated ND6 option found: type=%d\n",
246 __func__, nd_opt->nd_opt_type);
247 } else {
248 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
249 }
250 break;
251 case ND_OPT_PREFIX_INFO:
252 ndopts->nd_opts_pi_end = nd_opt;
253 if (!ndopts->nd_opt_array[nd_opt->nd_opt_type])
254 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
255 break;
256#ifdef CONFIG_IPV6_ROUTE_INFO
257 case ND_OPT_ROUTE_INFO:
258 ndopts->nd_opts_ri_end = nd_opt;
259 if (!ndopts->nd_opts_ri)
260 ndopts->nd_opts_ri = nd_opt;
261 break;
262#endif
263 default:
264 if (ndisc_is_useropt(dev, nd_opt)) {
265 ndopts->nd_useropts_end = nd_opt;
266 if (!ndopts->nd_useropts)
267 ndopts->nd_useropts = nd_opt;
268 } else {
269 /*
270 * Unknown options must be silently ignored,
271 * to accommodate future extension to the
272 * protocol.
273 */
274 ND_PRINTK(2, notice,
275 "%s: ignored unsupported option; type=%d, len=%d\n",
276 __func__,
277 nd_opt->nd_opt_type,
278 nd_opt->nd_opt_len);
279 }
280 }
281next_opt:
282 opt_len -= l;
283 nd_opt = ((void *)nd_opt) + l;
284 }
285 return ndopts;
286}
287
288int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
289{
290 switch (dev->type) {
291 case ARPHRD_ETHER:
292 case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */
293 case ARPHRD_FDDI:
294 ipv6_eth_mc_map(addr, buf);
295 return 0;
296 case ARPHRD_ARCNET:
297 ipv6_arcnet_mc_map(addr, buf);
298 return 0;
299 case ARPHRD_INFINIBAND:
300 ipv6_ib_mc_map(addr, dev->broadcast, buf);
301 return 0;
302 case ARPHRD_IPGRE:
303 return ipv6_ipgre_mc_map(addr, dev->broadcast, buf);
304 default:
305 if (dir) {
306 memcpy(buf, dev->broadcast, dev->addr_len);
307 return 0;
308 }
309 }
310 return -EINVAL;
311}
312EXPORT_SYMBOL(ndisc_mc_map);
313
314static u32 ndisc_hash(const void *pkey,
315 const struct net_device *dev,
316 __u32 *hash_rnd)
317{
318 return ndisc_hashfn(pkey, dev, hash_rnd);
319}
320
321static bool ndisc_key_eq(const struct neighbour *n, const void *pkey)
322{
323 return neigh_key_eq128(n, pkey);
324}
325
326static int ndisc_constructor(struct neighbour *neigh)
327{
328 struct in6_addr *addr = (struct in6_addr *)&neigh->primary_key;
329 struct net_device *dev = neigh->dev;
330 struct inet6_dev *in6_dev;
331 struct neigh_parms *parms;
332 bool is_multicast = ipv6_addr_is_multicast(addr);
333
334 in6_dev = in6_dev_get(dev);
335 if (!in6_dev) {
336 return -EINVAL;
337 }
338
339 parms = in6_dev->nd_parms;
340 __neigh_parms_put(neigh->parms);
341 neigh->parms = neigh_parms_clone(parms);
342
343 neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
344 if (!dev->header_ops) {
345 neigh->nud_state = NUD_NOARP;
346 neigh->ops = &ndisc_direct_ops;
347 neigh->output = neigh_direct_output;
348 } else {
349 if (is_multicast) {
350 neigh->nud_state = NUD_NOARP;
351 ndisc_mc_map(addr, neigh->ha, dev, 1);
352 } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
353 neigh->nud_state = NUD_NOARP;
354 memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
355 if (dev->flags&IFF_LOOPBACK)
356 neigh->type = RTN_LOCAL;
357 } else if (dev->flags&IFF_POINTOPOINT) {
358 neigh->nud_state = NUD_NOARP;
359 memcpy(neigh->ha, dev->broadcast, dev->addr_len);
360 }
361 if (dev->header_ops->cache)
362 neigh->ops = &ndisc_hh_ops;
363 else
364 neigh->ops = &ndisc_generic_ops;
365 if (neigh->nud_state&NUD_VALID)
366 neigh->output = neigh->ops->connected_output;
367 else
368 neigh->output = neigh->ops->output;
369 }
370 in6_dev_put(in6_dev);
371 return 0;
372}
373
374static int pndisc_constructor(struct pneigh_entry *n)
375{
376 struct in6_addr *addr = (struct in6_addr *)&n->key;
377 struct in6_addr maddr;
378 struct net_device *dev = n->dev;
379
380 if (!dev || !__in6_dev_get(dev))
381 return -EINVAL;
382 addrconf_addr_solict_mult(addr, &maddr);
383 ipv6_dev_mc_inc(dev, &maddr);
384 return 0;
385}
386
387static void pndisc_destructor(struct pneigh_entry *n)
388{
389 struct in6_addr *addr = (struct in6_addr *)&n->key;
390 struct in6_addr maddr;
391 struct net_device *dev = n->dev;
392
393 if (!dev || !__in6_dev_get(dev))
394 return;
395 addrconf_addr_solict_mult(addr, &maddr);
396 ipv6_dev_mc_dec(dev, &maddr);
397}
398
399/* called with rtnl held */
400static bool ndisc_allow_add(const struct net_device *dev,
401 struct netlink_ext_ack *extack)
402{
403 struct inet6_dev *idev = __in6_dev_get(dev);
404
405 if (!idev || idev->cnf.disable_ipv6) {
406 NL_SET_ERR_MSG(extack, "IPv6 is disabled on this device");
407 return false;
408 }
409
410 return true;
411}
412
413static struct sk_buff *ndisc_alloc_skb(struct net_device *dev,
414 int len)
415{
416 int hlen = LL_RESERVED_SPACE(dev);
417 int tlen = dev->needed_tailroom;
418 struct sock *sk = dev_net(dev)->ipv6.ndisc_sk;
419 struct sk_buff *skb;
420
421 skb = alloc_skb(hlen + sizeof(struct ipv6hdr) + len + tlen, GFP_ATOMIC);
422 if (!skb) {
423 ND_PRINTK(0, err, "ndisc: %s failed to allocate an skb\n",
424 __func__);
425 return NULL;
426 }
427
428 skb->protocol = htons(ETH_P_IPV6);
429 skb->dev = dev;
430
431 skb_reserve(skb, hlen + sizeof(struct ipv6hdr));
432 skb_reset_transport_header(skb);
433
434 /* Manually assign socket ownership as we avoid calling
435 * sock_alloc_send_pskb() to bypass wmem buffer limits
436 */
437 skb_set_owner_w(skb, sk);
438
439 return skb;
440}
441
442static void ip6_nd_hdr(struct sk_buff *skb,
443 const struct in6_addr *saddr,
444 const struct in6_addr *daddr,
445 int hop_limit, int len)
446{
447 struct ipv6hdr *hdr;
448 struct inet6_dev *idev;
449 unsigned tclass;
450
451 rcu_read_lock();
452 idev = __in6_dev_get(skb->dev);
453 tclass = idev ? idev->cnf.ndisc_tclass : 0;
454 rcu_read_unlock();
455
456 skb_push(skb, sizeof(*hdr));
457 skb_reset_network_header(skb);
458 hdr = ipv6_hdr(skb);
459
460 ip6_flow_hdr(hdr, tclass, 0);
461
462 hdr->payload_len = htons(len);
463 hdr->nexthdr = IPPROTO_ICMPV6;
464 hdr->hop_limit = hop_limit;
465
466 hdr->saddr = *saddr;
467 hdr->daddr = *daddr;
468}
469
470void ndisc_send_skb(struct sk_buff *skb, const struct in6_addr *daddr,
471 const struct in6_addr *saddr)
472{
473 struct dst_entry *dst = skb_dst(skb);
474 struct net *net = dev_net(skb->dev);
475 struct sock *sk = net->ipv6.ndisc_sk;
476 struct inet6_dev *idev;
477 int err;
478 struct icmp6hdr *icmp6h = icmp6_hdr(skb);
479 u8 type;
480
481 type = icmp6h->icmp6_type;
482
483 if (!dst) {
484 struct flowi6 fl6;
485 int oif = skb->dev->ifindex;
486
487 icmpv6_flow_init(sk, &fl6, type, saddr, daddr, oif);
488 dst = icmp6_dst_alloc(skb->dev, &fl6);
489 if (IS_ERR(dst)) {
490 kfree_skb(skb);
491 return;
492 }
493
494 skb_dst_set(skb, dst);
495 }
496
497 icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, skb->len,
498 IPPROTO_ICMPV6,
499 csum_partial(icmp6h,
500 skb->len, 0));
501
502 ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, skb->len);
503
504 rcu_read_lock();
505 idev = __in6_dev_get(dst->dev);
506 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
507
508 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
509 net, sk, skb, NULL, dst->dev,
510 dst_output);
511 if (!err) {
512 ICMP6MSGOUT_INC_STATS(net, idev, type);
513 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
514 }
515
516 rcu_read_unlock();
517}
518EXPORT_SYMBOL(ndisc_send_skb);
519
520void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr,
521 const struct in6_addr *solicited_addr,
522 bool router, bool solicited, bool override, bool inc_opt)
523{
524 struct sk_buff *skb;
525 struct in6_addr tmpaddr;
526 struct inet6_ifaddr *ifp;
527 const struct in6_addr *src_addr;
528 struct nd_msg *msg;
529 int optlen = 0;
530
531 /* for anycast or proxy, solicited_addr != src_addr */
532 ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1);
533 if (ifp) {
534 src_addr = solicited_addr;
535 if (ifp->flags & IFA_F_OPTIMISTIC)
536 override = false;
537 inc_opt |= ifp->idev->cnf.force_tllao;
538 in6_ifa_put(ifp);
539 } else {
540 if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr,
541 inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs,
542 &tmpaddr))
543 return;
544 src_addr = &tmpaddr;
545 }
546
547 if (!dev->addr_len)
548 inc_opt = false;
549 if (inc_opt)
550 optlen += ndisc_opt_addr_space(dev,
551 NDISC_NEIGHBOUR_ADVERTISEMENT);
552
553 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
554 if (!skb)
555 return;
556
557 msg = skb_put(skb, sizeof(*msg));
558 *msg = (struct nd_msg) {
559 .icmph = {
560 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
561 .icmp6_router = router,
562 .icmp6_solicited = solicited,
563 .icmp6_override = override,
564 },
565 .target = *solicited_addr,
566 };
567
568 if (inc_opt)
569 ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR,
570 dev->dev_addr,
571 NDISC_NEIGHBOUR_ADVERTISEMENT);
572
573 ndisc_send_skb(skb, daddr, src_addr);
574}
575
576static void ndisc_send_unsol_na(struct net_device *dev)
577{
578 struct inet6_dev *idev;
579 struct inet6_ifaddr *ifa;
580
581 idev = in6_dev_get(dev);
582 if (!idev)
583 return;
584
585 read_lock_bh(&idev->lock);
586 list_for_each_entry(ifa, &idev->addr_list, if_list) {
587 /* skip tentative addresses until dad completes */
588 if (ifa->flags & IFA_F_TENTATIVE &&
589 !(ifa->flags & IFA_F_OPTIMISTIC))
590 continue;
591
592 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &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
602struct sk_buff *ndisc_ns_create(struct net_device *dev, const struct in6_addr *solicit,
603 const struct in6_addr *saddr, u64 nonce)
604{
605 int inc_opt = dev->addr_len;
606 struct sk_buff *skb;
607 struct nd_msg *msg;
608 int optlen = 0;
609
610 if (!saddr)
611 return NULL;
612
613 if (ipv6_addr_any(saddr))
614 inc_opt = false;
615 if (inc_opt)
616 optlen += ndisc_opt_addr_space(dev,
617 NDISC_NEIGHBOUR_SOLICITATION);
618 if (nonce != 0)
619 optlen += 8;
620
621 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
622 if (!skb)
623 return NULL;
624
625 msg = skb_put(skb, sizeof(*msg));
626 *msg = (struct nd_msg) {
627 .icmph = {
628 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
629 },
630 .target = *solicit,
631 };
632
633 if (inc_opt)
634 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
635 dev->dev_addr,
636 NDISC_NEIGHBOUR_SOLICITATION);
637 if (nonce != 0) {
638 u8 *opt = skb_put(skb, 8);
639
640 opt[0] = ND_OPT_NONCE;
641 opt[1] = 8 >> 3;
642 memcpy(opt + 2, &nonce, 6);
643 }
644
645 return skb;
646}
647EXPORT_SYMBOL(ndisc_ns_create);
648
649void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit,
650 const struct in6_addr *daddr, const struct in6_addr *saddr,
651 u64 nonce)
652{
653 struct in6_addr addr_buf;
654 struct sk_buff *skb;
655
656 if (!saddr) {
657 if (ipv6_get_lladdr(dev, &addr_buf,
658 (IFA_F_TENTATIVE | IFA_F_OPTIMISTIC)))
659 return;
660 saddr = &addr_buf;
661 }
662
663 skb = ndisc_ns_create(dev, solicit, saddr, nonce);
664
665 if (skb)
666 ndisc_send_skb(skb, daddr, saddr);
667}
668
669void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr,
670 const struct in6_addr *daddr)
671{
672 struct sk_buff *skb;
673 struct rs_msg *msg;
674 int send_sllao = dev->addr_len;
675 int optlen = 0;
676
677#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
678 /*
679 * According to section 2.2 of RFC 4429, we must not
680 * send router solicitations with a sllao from
681 * optimistic addresses, but we may send the solicitation
682 * if we don't include the sllao. So here we check
683 * if our address is optimistic, and if so, we
684 * suppress the inclusion of the sllao.
685 */
686 if (send_sllao) {
687 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr,
688 dev, 1);
689 if (ifp) {
690 if (ifp->flags & IFA_F_OPTIMISTIC) {
691 send_sllao = 0;
692 }
693 in6_ifa_put(ifp);
694 } else {
695 send_sllao = 0;
696 }
697 }
698#endif
699 if (send_sllao)
700 optlen += ndisc_opt_addr_space(dev, NDISC_ROUTER_SOLICITATION);
701
702 skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
703 if (!skb)
704 return;
705
706 msg = skb_put(skb, sizeof(*msg));
707 *msg = (struct rs_msg) {
708 .icmph = {
709 .icmp6_type = NDISC_ROUTER_SOLICITATION,
710 },
711 };
712
713 if (send_sllao)
714 ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
715 dev->dev_addr,
716 NDISC_ROUTER_SOLICITATION);
717
718 ndisc_send_skb(skb, daddr, saddr);
719}
720
721
722static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
723{
724 /*
725 * "The sender MUST return an ICMP
726 * destination unreachable"
727 */
728 dst_link_failure(skb);
729 kfree_skb(skb);
730}
731
732/* Called with locked neigh: either read or both */
733
734static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
735{
736 struct in6_addr *saddr = NULL;
737 struct in6_addr mcaddr;
738 struct net_device *dev = neigh->dev;
739 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
740 int probes = atomic_read(&neigh->probes);
741
742 if (skb && ipv6_chk_addr_and_flags(dev_net(dev), &ipv6_hdr(skb)->saddr,
743 dev, false, 1,
744 IFA_F_TENTATIVE|IFA_F_OPTIMISTIC))
745 saddr = &ipv6_hdr(skb)->saddr;
746 probes -= NEIGH_VAR(neigh->parms, UCAST_PROBES);
747 if (probes < 0) {
748 if (!(neigh->nud_state & NUD_VALID)) {
749 ND_PRINTK(1, dbg,
750 "%s: trying to ucast probe in NUD_INVALID: %pI6\n",
751 __func__, target);
752 }
753 ndisc_send_ns(dev, target, target, saddr, 0);
754 } else if ((probes -= NEIGH_VAR(neigh->parms, APP_PROBES)) < 0) {
755 neigh_app_ns(neigh);
756 } else {
757 addrconf_addr_solict_mult(target, &mcaddr);
758 ndisc_send_ns(dev, target, &mcaddr, saddr, 0);
759 }
760}
761
762static int pndisc_is_router(const void *pkey,
763 struct net_device *dev)
764{
765 struct pneigh_entry *n;
766 int ret = -1;
767
768 read_lock_bh(&nd_tbl.lock);
769 n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev);
770 if (n)
771 ret = !!(n->flags & NTF_ROUTER);
772 read_unlock_bh(&nd_tbl.lock);
773
774 return ret;
775}
776
777void ndisc_update(const struct net_device *dev, struct neighbour *neigh,
778 const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type,
779 struct ndisc_options *ndopts)
780{
781 neigh_update(neigh, lladdr, new, flags, 0);
782 /* report ndisc ops about neighbour update */
783 ndisc_ops_update(dev, neigh, flags, icmp6_type, ndopts);
784}
785
786static void ndisc_recv_ns(struct sk_buff *skb)
787{
788 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
789 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
790 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
791 u8 *lladdr = NULL;
792 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
793 offsetof(struct nd_msg, opt));
794 struct ndisc_options ndopts;
795 struct net_device *dev = skb->dev;
796 struct inet6_ifaddr *ifp;
797 struct inet6_dev *idev = NULL;
798 struct neighbour *neigh;
799 int dad = ipv6_addr_any(saddr);
800 bool inc;
801 int is_router = -1;
802 u64 nonce = 0;
803
804 if (skb->len < sizeof(struct nd_msg)) {
805 ND_PRINTK(2, warn, "NS: packet too short\n");
806 return;
807 }
808
809 if (ipv6_addr_is_multicast(&msg->target)) {
810 ND_PRINTK(2, warn, "NS: multicast target address\n");
811 return;
812 }
813
814 /*
815 * RFC2461 7.1.1:
816 * DAD has to be destined for solicited node multicast address.
817 */
818 if (dad && !ipv6_addr_is_solict_mult(daddr)) {
819 ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n");
820 return;
821 }
822
823 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) {
824 ND_PRINTK(2, warn, "NS: invalid ND options\n");
825 return;
826 }
827
828 if (ndopts.nd_opts_src_lladdr) {
829 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
830 if (!lladdr) {
831 ND_PRINTK(2, warn,
832 "NS: invalid link-layer address length\n");
833 return;
834 }
835
836 /* RFC2461 7.1.1:
837 * If the IP source address is the unspecified address,
838 * there MUST NOT be source link-layer address option
839 * in the message.
840 */
841 if (dad) {
842 ND_PRINTK(2, warn,
843 "NS: bad DAD packet (link-layer address option)\n");
844 return;
845 }
846 }
847 if (ndopts.nd_opts_nonce && ndopts.nd_opts_nonce->nd_opt_len == 1)
848 memcpy(&nonce, (u8 *)(ndopts.nd_opts_nonce + 1), 6);
849
850 inc = ipv6_addr_is_multicast(daddr);
851
852 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
853 if (ifp) {
854have_ifp:
855 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
856 if (dad) {
857 if (nonce != 0 && ifp->dad_nonce == nonce) {
858 u8 *np = (u8 *)&nonce;
859 /* Matching nonce if looped back */
860 ND_PRINTK(2, notice,
861 "%s: IPv6 DAD loopback for address %pI6c nonce %pM ignored\n",
862 ifp->idev->dev->name,
863 &ifp->addr, np);
864 goto out;
865 }
866 /*
867 * We are colliding with another node
868 * who is doing DAD
869 * so fail our DAD process
870 */
871 addrconf_dad_failure(skb, ifp);
872 return;
873 } else {
874 /*
875 * This is not a dad solicitation.
876 * If we are an optimistic node,
877 * we should respond.
878 * Otherwise, we should ignore it.
879 */
880 if (!(ifp->flags & IFA_F_OPTIMISTIC))
881 goto out;
882 }
883 }
884
885 idev = ifp->idev;
886 } else {
887 struct net *net = dev_net(dev);
888
889 /* perhaps an address on the master device */
890 if (netif_is_l3_slave(dev)) {
891 struct net_device *mdev;
892
893 mdev = netdev_master_upper_dev_get_rcu(dev);
894 if (mdev) {
895 ifp = ipv6_get_ifaddr(net, &msg->target, mdev, 1);
896 if (ifp)
897 goto have_ifp;
898 }
899 }
900
901 idev = in6_dev_get(dev);
902 if (!idev) {
903 /* XXX: count this drop? */
904 return;
905 }
906
907 if (ipv6_chk_acast_addr(net, dev, &msg->target) ||
908 (idev->cnf.forwarding &&
909 (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) &&
910 (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) {
911 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
912 skb->pkt_type != PACKET_HOST &&
913 inc &&
914 NEIGH_VAR(idev->nd_parms, PROXY_DELAY) != 0) {
915 /*
916 * for anycast or proxy,
917 * sender should delay its response
918 * by a random time between 0 and
919 * MAX_ANYCAST_DELAY_TIME seconds.
920 * (RFC2461) -- yoshfuji
921 */
922 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
923 if (n)
924 pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
925 goto out;
926 }
927 } else
928 goto out;
929 }
930
931 if (is_router < 0)
932 is_router = idev->cnf.forwarding;
933
934 if (dad) {
935 ndisc_send_na(dev, &in6addr_linklocal_allnodes, &msg->target,
936 !!is_router, false, (ifp != NULL), true);
937 goto out;
938 }
939
940 if (inc)
941 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
942 else
943 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
944
945 /*
946 * update / create cache entry
947 * for the source address
948 */
949 neigh = __neigh_lookup(&nd_tbl, saddr, dev,
950 !inc || lladdr || !dev->addr_len);
951 if (neigh)
952 ndisc_update(dev, neigh, lladdr, NUD_STALE,
953 NEIGH_UPDATE_F_WEAK_OVERRIDE|
954 NEIGH_UPDATE_F_OVERRIDE,
955 NDISC_NEIGHBOUR_SOLICITATION, &ndopts);
956 if (neigh || !dev->header_ops) {
957 ndisc_send_na(dev, saddr, &msg->target, !!is_router,
958 true, (ifp != NULL && inc), inc);
959 if (neigh)
960 neigh_release(neigh);
961 }
962
963out:
964 if (ifp)
965 in6_ifa_put(ifp);
966 else
967 in6_dev_put(idev);
968}
969
970static int accept_untracked_na(struct net_device *dev, struct in6_addr *saddr)
971{
972 struct inet6_dev *idev = __in6_dev_get(dev);
973
974 switch (idev->cnf.accept_untracked_na) {
975 case 0: /* Don't accept untracked na (absent in neighbor cache) */
976 return 0;
977 case 1: /* Create new entries from na if currently untracked */
978 return 1;
979 case 2: /* Create new entries from untracked na only if saddr is in the
980 * same subnet as an address configured on the interface that
981 * received the na
982 */
983 return !!ipv6_chk_prefix(saddr, dev);
984 default:
985 return 0;
986 }
987}
988
989static void ndisc_recv_na(struct sk_buff *skb)
990{
991 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
992 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
993 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
994 u8 *lladdr = NULL;
995 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
996 offsetof(struct nd_msg, opt));
997 struct ndisc_options ndopts;
998 struct net_device *dev = skb->dev;
999 struct inet6_dev *idev = __in6_dev_get(dev);
1000 struct inet6_ifaddr *ifp;
1001 struct neighbour *neigh;
1002 u8 new_state;
1003
1004 if (skb->len < sizeof(struct nd_msg)) {
1005 ND_PRINTK(2, warn, "NA: packet too short\n");
1006 return;
1007 }
1008
1009 if (ipv6_addr_is_multicast(&msg->target)) {
1010 ND_PRINTK(2, warn, "NA: target address is multicast\n");
1011 return;
1012 }
1013
1014 if (ipv6_addr_is_multicast(daddr) &&
1015 msg->icmph.icmp6_solicited) {
1016 ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n");
1017 return;
1018 }
1019
1020 /* For some 802.11 wireless deployments (and possibly other networks),
1021 * there will be a NA proxy and unsolicitd packets are attacks
1022 * and thus should not be accepted.
1023 * drop_unsolicited_na takes precedence over accept_untracked_na
1024 */
1025 if (!msg->icmph.icmp6_solicited && idev &&
1026 idev->cnf.drop_unsolicited_na)
1027 return;
1028
1029 if (!ndisc_parse_options(dev, msg->opt, ndoptlen, &ndopts)) {
1030 ND_PRINTK(2, warn, "NS: invalid ND option\n");
1031 return;
1032 }
1033 if (ndopts.nd_opts_tgt_lladdr) {
1034 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
1035 if (!lladdr) {
1036 ND_PRINTK(2, warn,
1037 "NA: invalid link-layer address length\n");
1038 return;
1039 }
1040 }
1041 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
1042 if (ifp) {
1043 if (skb->pkt_type != PACKET_LOOPBACK
1044 && (ifp->flags & IFA_F_TENTATIVE)) {
1045 addrconf_dad_failure(skb, ifp);
1046 return;
1047 }
1048 /* What should we make now? The advertisement
1049 is invalid, but ndisc specs say nothing
1050 about it. It could be misconfiguration, or
1051 an smart proxy agent tries to help us :-)
1052
1053 We should not print the error if NA has been
1054 received from loopback - it is just our own
1055 unsolicited advertisement.
1056 */
1057 if (skb->pkt_type != PACKET_LOOPBACK)
1058 ND_PRINTK(1, warn,
1059 "NA: %pM advertised our address %pI6c on %s!\n",
1060 eth_hdr(skb)->h_source, &ifp->addr, ifp->idev->dev->name);
1061 in6_ifa_put(ifp);
1062 return;
1063 }
1064
1065 neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
1066
1067 /* RFC 9131 updates original Neighbour Discovery RFC 4861.
1068 * NAs with Target LL Address option without a corresponding
1069 * entry in the neighbour cache can now create a STALE neighbour
1070 * cache entry on routers.
1071 *
1072 * entry accept fwding solicited behaviour
1073 * ------- ------ ------ --------- ----------------------
1074 * present X X 0 Set state to STALE
1075 * present X X 1 Set state to REACHABLE
1076 * absent 0 X X Do nothing
1077 * absent 1 0 X Do nothing
1078 * absent 1 1 X Add a new STALE entry
1079 *
1080 * Note that we don't do a (daddr == all-routers-mcast) check.
1081 */
1082 new_state = msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE;
1083 if (!neigh && lladdr && idev && idev->cnf.forwarding) {
1084 if (accept_untracked_na(dev, saddr)) {
1085 neigh = neigh_create(&nd_tbl, &msg->target, dev);
1086 new_state = NUD_STALE;
1087 }
1088 }
1089
1090 if (neigh && !IS_ERR(neigh)) {
1091 u8 old_flags = neigh->flags;
1092 struct net *net = dev_net(dev);
1093
1094 if (neigh->nud_state & NUD_FAILED)
1095 goto out;
1096
1097 /*
1098 * Don't update the neighbor cache entry on a proxy NA from
1099 * ourselves because either the proxied node is off link or it
1100 * has already sent a NA to us.
1101 */
1102 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
1103 net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp &&
1104 pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) {
1105 /* XXX: idev->cnf.proxy_ndp */
1106 goto out;
1107 }
1108
1109 ndisc_update(dev, neigh, lladdr,
1110 new_state,
1111 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1112 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
1113 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1114 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0),
1115 NDISC_NEIGHBOUR_ADVERTISEMENT, &ndopts);
1116
1117 if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
1118 /*
1119 * Change: router to host
1120 */
1121 rt6_clean_tohost(dev_net(dev), saddr);
1122 }
1123
1124out:
1125 neigh_release(neigh);
1126 }
1127}
1128
1129static void ndisc_recv_rs(struct sk_buff *skb)
1130{
1131 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
1132 unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
1133 struct neighbour *neigh;
1134 struct inet6_dev *idev;
1135 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
1136 struct ndisc_options ndopts;
1137 u8 *lladdr = NULL;
1138
1139 if (skb->len < sizeof(*rs_msg))
1140 return;
1141
1142 idev = __in6_dev_get(skb->dev);
1143 if (!idev) {
1144 ND_PRINTK(1, err, "RS: can't find in6 device\n");
1145 return;
1146 }
1147
1148 /* Don't accept RS if we're not in router mode */
1149 if (!idev->cnf.forwarding)
1150 goto out;
1151
1152 /*
1153 * Don't update NCE if src = ::;
1154 * this implies that the source node has no ip address assigned yet.
1155 */
1156 if (ipv6_addr_any(saddr))
1157 goto out;
1158
1159 /* Parse ND options */
1160 if (!ndisc_parse_options(skb->dev, rs_msg->opt, ndoptlen, &ndopts)) {
1161 ND_PRINTK(2, notice, "NS: invalid ND option, ignored\n");
1162 goto out;
1163 }
1164
1165 if (ndopts.nd_opts_src_lladdr) {
1166 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1167 skb->dev);
1168 if (!lladdr)
1169 goto out;
1170 }
1171
1172 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
1173 if (neigh) {
1174 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
1175 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1176 NEIGH_UPDATE_F_OVERRIDE|
1177 NEIGH_UPDATE_F_OVERRIDE_ISROUTER,
1178 NDISC_ROUTER_SOLICITATION, &ndopts);
1179 neigh_release(neigh);
1180 }
1181out:
1182 return;
1183}
1184
1185static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
1186{
1187 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
1188 struct sk_buff *skb;
1189 struct nlmsghdr *nlh;
1190 struct nduseroptmsg *ndmsg;
1191 struct net *net = dev_net(ra->dev);
1192 int err;
1193 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
1194 + (opt->nd_opt_len << 3));
1195 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
1196
1197 skb = nlmsg_new(msg_size, GFP_ATOMIC);
1198 if (!skb) {
1199 err = -ENOBUFS;
1200 goto errout;
1201 }
1202
1203 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
1204 if (!nlh) {
1205 goto nla_put_failure;
1206 }
1207
1208 ndmsg = nlmsg_data(nlh);
1209 ndmsg->nduseropt_family = AF_INET6;
1210 ndmsg->nduseropt_ifindex = ra->dev->ifindex;
1211 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
1212 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
1213 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
1214
1215 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
1216
1217 if (nla_put_in6_addr(skb, NDUSEROPT_SRCADDR, &ipv6_hdr(ra)->saddr))
1218 goto nla_put_failure;
1219 nlmsg_end(skb, nlh);
1220
1221 rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC);
1222 return;
1223
1224nla_put_failure:
1225 nlmsg_free(skb);
1226 err = -EMSGSIZE;
1227errout:
1228 rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err);
1229}
1230
1231static void ndisc_router_discovery(struct sk_buff *skb)
1232{
1233 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
1234 struct neighbour *neigh = NULL;
1235 struct inet6_dev *in6_dev;
1236 struct fib6_info *rt = NULL;
1237 u32 defrtr_usr_metric;
1238 struct net *net;
1239 int lifetime;
1240 struct ndisc_options ndopts;
1241 int optlen;
1242 unsigned int pref = 0;
1243 __u32 old_if_flags;
1244 bool send_ifinfo_notify = false;
1245
1246 __u8 *opt = (__u8 *)(ra_msg + 1);
1247
1248 optlen = (skb_tail_pointer(skb) - skb_transport_header(skb)) -
1249 sizeof(struct ra_msg);
1250
1251 ND_PRINTK(2, info,
1252 "RA: %s, dev: %s\n",
1253 __func__, skb->dev->name);
1254 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1255 ND_PRINTK(2, warn, "RA: source address is not link-local\n");
1256 return;
1257 }
1258 if (optlen < 0) {
1259 ND_PRINTK(2, warn, "RA: packet too short\n");
1260 return;
1261 }
1262
1263#ifdef CONFIG_IPV6_NDISC_NODETYPE
1264 if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) {
1265 ND_PRINTK(2, warn, "RA: from host or unauthorized router\n");
1266 return;
1267 }
1268#endif
1269
1270 /*
1271 * set the RA_RECV flag in the interface
1272 */
1273
1274 in6_dev = __in6_dev_get(skb->dev);
1275 if (!in6_dev) {
1276 ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n",
1277 skb->dev->name);
1278 return;
1279 }
1280
1281 if (!ndisc_parse_options(skb->dev, opt, optlen, &ndopts)) {
1282 ND_PRINTK(2, warn, "RA: invalid ND options\n");
1283 return;
1284 }
1285
1286 if (!ipv6_accept_ra(in6_dev)) {
1287 ND_PRINTK(2, info,
1288 "RA: %s, did not accept ra for dev: %s\n",
1289 __func__, skb->dev->name);
1290 goto skip_linkparms;
1291 }
1292
1293#ifdef CONFIG_IPV6_NDISC_NODETYPE
1294 /* skip link-specific parameters from interior routers */
1295 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) {
1296 ND_PRINTK(2, info,
1297 "RA: %s, nodetype is NODEFAULT, dev: %s\n",
1298 __func__, skb->dev->name);
1299 goto skip_linkparms;
1300 }
1301#endif
1302
1303 if (in6_dev->if_flags & IF_RS_SENT) {
1304 /*
1305 * flag that an RA was received after an RS was sent
1306 * out on this interface.
1307 */
1308 in6_dev->if_flags |= IF_RA_RCVD;
1309 }
1310
1311 /*
1312 * Remember the managed/otherconf flags from most recently
1313 * received RA message (RFC 2462) -- yoshfuji
1314 */
1315 old_if_flags = in6_dev->if_flags;
1316 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1317 IF_RA_OTHERCONF)) |
1318 (ra_msg->icmph.icmp6_addrconf_managed ?
1319 IF_RA_MANAGED : 0) |
1320 (ra_msg->icmph.icmp6_addrconf_other ?
1321 IF_RA_OTHERCONF : 0);
1322
1323 if (old_if_flags != in6_dev->if_flags)
1324 send_ifinfo_notify = true;
1325
1326 if (!in6_dev->cnf.accept_ra_defrtr) {
1327 ND_PRINTK(2, info,
1328 "RA: %s, defrtr is false for dev: %s\n",
1329 __func__, skb->dev->name);
1330 goto skip_defrtr;
1331 }
1332
1333 /* Do not accept RA with source-addr found on local machine unless
1334 * accept_ra_from_local is set to true.
1335 */
1336 net = dev_net(in6_dev->dev);
1337 if (!in6_dev->cnf.accept_ra_from_local &&
1338 ipv6_chk_addr(net, &ipv6_hdr(skb)->saddr, in6_dev->dev, 0)) {
1339 ND_PRINTK(2, info,
1340 "RA from local address detected on dev: %s: default router ignored\n",
1341 skb->dev->name);
1342 goto skip_defrtr;
1343 }
1344
1345 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1346
1347#ifdef CONFIG_IPV6_ROUTER_PREF
1348 pref = ra_msg->icmph.icmp6_router_pref;
1349 /* 10b is handled as if it were 00b (medium) */
1350 if (pref == ICMPV6_ROUTER_PREF_INVALID ||
1351 !in6_dev->cnf.accept_ra_rtr_pref)
1352 pref = ICMPV6_ROUTER_PREF_MEDIUM;
1353#endif
1354 /* routes added from RAs do not use nexthop objects */
1355 rt = rt6_get_dflt_router(net, &ipv6_hdr(skb)->saddr, skb->dev);
1356 if (rt) {
1357 neigh = ip6_neigh_lookup(&rt->fib6_nh->fib_nh_gw6,
1358 rt->fib6_nh->fib_nh_dev, NULL,
1359 &ipv6_hdr(skb)->saddr);
1360 if (!neigh) {
1361 ND_PRINTK(0, err,
1362 "RA: %s got default router without neighbour\n",
1363 __func__);
1364 fib6_info_release(rt);
1365 return;
1366 }
1367 }
1368 /* Set default route metric as specified by user */
1369 defrtr_usr_metric = in6_dev->cnf.ra_defrtr_metric;
1370 /* delete the route if lifetime is 0 or if metric needs change */
1371 if (rt && (lifetime == 0 || rt->fib6_metric != defrtr_usr_metric)) {
1372 ip6_del_rt(net, rt, false);
1373 rt = NULL;
1374 }
1375
1376 ND_PRINTK(3, info, "RA: rt: %p lifetime: %d, metric: %d, for dev: %s\n",
1377 rt, lifetime, defrtr_usr_metric, skb->dev->name);
1378 if (!rt && lifetime) {
1379 ND_PRINTK(3, info, "RA: adding default router\n");
1380
1381 if (neigh)
1382 neigh_release(neigh);
1383
1384 rt = rt6_add_dflt_router(net, &ipv6_hdr(skb)->saddr,
1385 skb->dev, pref, defrtr_usr_metric);
1386 if (!rt) {
1387 ND_PRINTK(0, err,
1388 "RA: %s failed to add default route\n",
1389 __func__);
1390 return;
1391 }
1392
1393 neigh = ip6_neigh_lookup(&rt->fib6_nh->fib_nh_gw6,
1394 rt->fib6_nh->fib_nh_dev, NULL,
1395 &ipv6_hdr(skb)->saddr);
1396 if (!neigh) {
1397 ND_PRINTK(0, err,
1398 "RA: %s got default router without neighbour\n",
1399 __func__);
1400 fib6_info_release(rt);
1401 return;
1402 }
1403 neigh->flags |= NTF_ROUTER;
1404 } else if (rt && IPV6_EXTRACT_PREF(rt->fib6_flags) != pref) {
1405 struct nl_info nlinfo = {
1406 .nl_net = net,
1407 };
1408 rt->fib6_flags = (rt->fib6_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
1409 inet6_rt_notify(RTM_NEWROUTE, rt, &nlinfo, NLM_F_REPLACE);
1410 }
1411
1412 if (rt)
1413 fib6_set_expires(rt, jiffies + (HZ * lifetime));
1414 if (in6_dev->cnf.accept_ra_min_hop_limit < 256 &&
1415 ra_msg->icmph.icmp6_hop_limit) {
1416 if (in6_dev->cnf.accept_ra_min_hop_limit <= ra_msg->icmph.icmp6_hop_limit) {
1417 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
1418 fib6_metric_set(rt, RTAX_HOPLIMIT,
1419 ra_msg->icmph.icmp6_hop_limit);
1420 } else {
1421 ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than minimum\n");
1422 }
1423 }
1424
1425skip_defrtr:
1426
1427 /*
1428 * Update Reachable Time and Retrans Timer
1429 */
1430
1431 if (in6_dev->nd_parms) {
1432 unsigned long rtime = ntohl(ra_msg->retrans_timer);
1433
1434 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1435 rtime = (rtime*HZ)/1000;
1436 if (rtime < HZ/100)
1437 rtime = HZ/100;
1438 NEIGH_VAR_SET(in6_dev->nd_parms, RETRANS_TIME, rtime);
1439 in6_dev->tstamp = jiffies;
1440 send_ifinfo_notify = true;
1441 }
1442
1443 rtime = ntohl(ra_msg->reachable_time);
1444 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1445 rtime = (rtime*HZ)/1000;
1446
1447 if (rtime < HZ/10)
1448 rtime = HZ/10;
1449
1450 if (rtime != NEIGH_VAR(in6_dev->nd_parms, BASE_REACHABLE_TIME)) {
1451 NEIGH_VAR_SET(in6_dev->nd_parms,
1452 BASE_REACHABLE_TIME, rtime);
1453 NEIGH_VAR_SET(in6_dev->nd_parms,
1454 GC_STALETIME, 3 * rtime);
1455 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1456 in6_dev->tstamp = jiffies;
1457 send_ifinfo_notify = true;
1458 }
1459 }
1460 }
1461
1462skip_linkparms:
1463
1464 /*
1465 * Process options.
1466 */
1467
1468 if (!neigh)
1469 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
1470 skb->dev, 1);
1471 if (neigh) {
1472 u8 *lladdr = NULL;
1473 if (ndopts.nd_opts_src_lladdr) {
1474 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1475 skb->dev);
1476 if (!lladdr) {
1477 ND_PRINTK(2, warn,
1478 "RA: invalid link-layer address length\n");
1479 goto out;
1480 }
1481 }
1482 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
1483 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1484 NEIGH_UPDATE_F_OVERRIDE|
1485 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1486 NEIGH_UPDATE_F_ISROUTER,
1487 NDISC_ROUTER_ADVERTISEMENT, &ndopts);
1488 }
1489
1490 if (!ipv6_accept_ra(in6_dev)) {
1491 ND_PRINTK(2, info,
1492 "RA: %s, accept_ra is false for dev: %s\n",
1493 __func__, skb->dev->name);
1494 goto out;
1495 }
1496
1497#ifdef CONFIG_IPV6_ROUTE_INFO
1498 if (!in6_dev->cnf.accept_ra_from_local &&
1499 ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr,
1500 in6_dev->dev, 0)) {
1501 ND_PRINTK(2, info,
1502 "RA from local address detected on dev: %s: router info ignored.\n",
1503 skb->dev->name);
1504 goto skip_routeinfo;
1505 }
1506
1507 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
1508 struct nd_opt_hdr *p;
1509 for (p = ndopts.nd_opts_ri;
1510 p;
1511 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
1512 struct route_info *ri = (struct route_info *)p;
1513#ifdef CONFIG_IPV6_NDISC_NODETYPE
1514 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT &&
1515 ri->prefix_len == 0)
1516 continue;
1517#endif
1518 if (ri->prefix_len == 0 &&
1519 !in6_dev->cnf.accept_ra_defrtr)
1520 continue;
1521 if (ri->prefix_len < in6_dev->cnf.accept_ra_rt_info_min_plen)
1522 continue;
1523 if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
1524 continue;
1525 rt6_route_rcv(skb->dev, (u8 *)p, (p->nd_opt_len) << 3,
1526 &ipv6_hdr(skb)->saddr);
1527 }
1528 }
1529
1530skip_routeinfo:
1531#endif
1532
1533#ifdef CONFIG_IPV6_NDISC_NODETYPE
1534 /* skip link-specific ndopts from interior routers */
1535 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) {
1536 ND_PRINTK(2, info,
1537 "RA: %s, nodetype is NODEFAULT (interior routes), dev: %s\n",
1538 __func__, skb->dev->name);
1539 goto out;
1540 }
1541#endif
1542
1543 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
1544 struct nd_opt_hdr *p;
1545 for (p = ndopts.nd_opts_pi;
1546 p;
1547 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1548 addrconf_prefix_rcv(skb->dev, (u8 *)p,
1549 (p->nd_opt_len) << 3,
1550 ndopts.nd_opts_src_lladdr != NULL);
1551 }
1552 }
1553
1554 if (ndopts.nd_opts_mtu && in6_dev->cnf.accept_ra_mtu) {
1555 __be32 n;
1556 u32 mtu;
1557
1558 memcpy(&n, ((u8 *)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1559 mtu = ntohl(n);
1560
1561 if (in6_dev->ra_mtu != mtu) {
1562 in6_dev->ra_mtu = mtu;
1563 send_ifinfo_notify = true;
1564 }
1565
1566 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1567 ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu);
1568 } else if (in6_dev->cnf.mtu6 != mtu) {
1569 in6_dev->cnf.mtu6 = mtu;
1570 fib6_metric_set(rt, RTAX_MTU, mtu);
1571 rt6_mtu_change(skb->dev, mtu);
1572 }
1573 }
1574
1575 if (ndopts.nd_useropts) {
1576 struct nd_opt_hdr *p;
1577 for (p = ndopts.nd_useropts;
1578 p;
1579 p = ndisc_next_useropt(skb->dev, p,
1580 ndopts.nd_useropts_end)) {
1581 ndisc_ra_useropt(skb, p);
1582 }
1583 }
1584
1585 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1586 ND_PRINTK(2, warn, "RA: invalid RA options\n");
1587 }
1588out:
1589 /* Send a notify if RA changed managed/otherconf flags or
1590 * timer settings or ra_mtu value
1591 */
1592 if (send_ifinfo_notify)
1593 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1594
1595 fib6_info_release(rt);
1596 if (neigh)
1597 neigh_release(neigh);
1598}
1599
1600static void ndisc_redirect_rcv(struct sk_buff *skb)
1601{
1602 u8 *hdr;
1603 struct ndisc_options ndopts;
1604 struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb);
1605 u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
1606 offsetof(struct rd_msg, opt));
1607
1608#ifdef CONFIG_IPV6_NDISC_NODETYPE
1609 switch (skb->ndisc_nodetype) {
1610 case NDISC_NODETYPE_HOST:
1611 case NDISC_NODETYPE_NODEFAULT:
1612 ND_PRINTK(2, warn,
1613 "Redirect: from host or unauthorized router\n");
1614 return;
1615 }
1616#endif
1617
1618 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1619 ND_PRINTK(2, warn,
1620 "Redirect: source address is not link-local\n");
1621 return;
1622 }
1623
1624 if (!ndisc_parse_options(skb->dev, msg->opt, ndoptlen, &ndopts))
1625 return;
1626
1627 if (!ndopts.nd_opts_rh) {
1628 ip6_redirect_no_header(skb, dev_net(skb->dev),
1629 skb->dev->ifindex);
1630 return;
1631 }
1632
1633 hdr = (u8 *)ndopts.nd_opts_rh;
1634 hdr += 8;
1635 if (!pskb_pull(skb, hdr - skb_transport_header(skb)))
1636 return;
1637
1638 icmpv6_notify(skb, NDISC_REDIRECT, 0, 0);
1639}
1640
1641static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb,
1642 struct sk_buff *orig_skb,
1643 int rd_len)
1644{
1645 u8 *opt = skb_put(skb, rd_len);
1646
1647 memset(opt, 0, 8);
1648 *(opt++) = ND_OPT_REDIRECT_HDR;
1649 *(opt++) = (rd_len >> 3);
1650 opt += 6;
1651
1652 skb_copy_bits(orig_skb, skb_network_offset(orig_skb), opt,
1653 rd_len - 8);
1654}
1655
1656void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
1657{
1658 struct net_device *dev = skb->dev;
1659 struct net *net = dev_net(dev);
1660 struct sock *sk = net->ipv6.ndisc_sk;
1661 int optlen = 0;
1662 struct inet_peer *peer;
1663 struct sk_buff *buff;
1664 struct rd_msg *msg;
1665 struct in6_addr saddr_buf;
1666 struct rt6_info *rt;
1667 struct dst_entry *dst;
1668 struct flowi6 fl6;
1669 int rd_len;
1670 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL,
1671 ops_data_buf[NDISC_OPS_REDIRECT_DATA_SPACE], *ops_data = NULL;
1672 bool ret;
1673
1674 if (netif_is_l3_master(skb->dev)) {
1675 dev = __dev_get_by_index(dev_net(skb->dev), IPCB(skb)->iif);
1676 if (!dev)
1677 return;
1678 }
1679
1680 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
1681 ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n",
1682 dev->name);
1683 return;
1684 }
1685
1686 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
1687 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1688 ND_PRINTK(2, warn,
1689 "Redirect: target address is not link-local unicast\n");
1690 return;
1691 }
1692
1693 icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT,
1694 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex);
1695
1696 dst = ip6_route_output(net, NULL, &fl6);
1697 if (dst->error) {
1698 dst_release(dst);
1699 return;
1700 }
1701 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
1702 if (IS_ERR(dst))
1703 return;
1704
1705 rt = (struct rt6_info *) dst;
1706
1707 if (rt->rt6i_flags & RTF_GATEWAY) {
1708 ND_PRINTK(2, warn,
1709 "Redirect: destination is not a neighbour\n");
1710 goto release;
1711 }
1712 peer = inet_getpeer_v6(net->ipv6.peers, &ipv6_hdr(skb)->saddr, 1);
1713 ret = inet_peer_xrlim_allow(peer, 1*HZ);
1714 if (peer)
1715 inet_putpeer(peer);
1716 if (!ret)
1717 goto release;
1718
1719 if (dev->addr_len) {
1720 struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target);
1721 if (!neigh) {
1722 ND_PRINTK(2, warn,
1723 "Redirect: no neigh for target address\n");
1724 goto release;
1725 }
1726
1727 read_lock_bh(&neigh->lock);
1728 if (neigh->nud_state & NUD_VALID) {
1729 memcpy(ha_buf, neigh->ha, dev->addr_len);
1730 read_unlock_bh(&neigh->lock);
1731 ha = ha_buf;
1732 optlen += ndisc_redirect_opt_addr_space(dev, neigh,
1733 ops_data_buf,
1734 &ops_data);
1735 } else
1736 read_unlock_bh(&neigh->lock);
1737
1738 neigh_release(neigh);
1739 }
1740
1741 rd_len = min_t(unsigned int,
1742 IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen,
1743 skb->len + 8);
1744 rd_len &= ~0x7;
1745 optlen += rd_len;
1746
1747 buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
1748 if (!buff)
1749 goto release;
1750
1751 msg = skb_put(buff, sizeof(*msg));
1752 *msg = (struct rd_msg) {
1753 .icmph = {
1754 .icmp6_type = NDISC_REDIRECT,
1755 },
1756 .target = *target,
1757 .dest = ipv6_hdr(skb)->daddr,
1758 };
1759
1760 /*
1761 * include target_address option
1762 */
1763
1764 if (ha)
1765 ndisc_fill_redirect_addr_option(buff, ha, ops_data);
1766
1767 /*
1768 * build redirect option and copy skb over to the new packet.
1769 */
1770
1771 if (rd_len)
1772 ndisc_fill_redirect_hdr_option(buff, skb, rd_len);
1773
1774 skb_dst_set(buff, dst);
1775 ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf);
1776 return;
1777
1778release:
1779 dst_release(dst);
1780}
1781
1782static void pndisc_redo(struct sk_buff *skb)
1783{
1784 ndisc_recv_ns(skb);
1785 kfree_skb(skb);
1786}
1787
1788static int ndisc_is_multicast(const void *pkey)
1789{
1790 return ipv6_addr_is_multicast((struct in6_addr *)pkey);
1791}
1792
1793static bool ndisc_suppress_frag_ndisc(struct sk_buff *skb)
1794{
1795 struct inet6_dev *idev = __in6_dev_get(skb->dev);
1796
1797 if (!idev)
1798 return true;
1799 if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED &&
1800 idev->cnf.suppress_frag_ndisc) {
1801 net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n");
1802 return true;
1803 }
1804 return false;
1805}
1806
1807int ndisc_rcv(struct sk_buff *skb)
1808{
1809 struct nd_msg *msg;
1810
1811 if (ndisc_suppress_frag_ndisc(skb))
1812 return 0;
1813
1814 if (skb_linearize(skb))
1815 return 0;
1816
1817 msg = (struct nd_msg *)skb_transport_header(skb);
1818
1819 __skb_push(skb, skb->data - skb_transport_header(skb));
1820
1821 if (ipv6_hdr(skb)->hop_limit != 255) {
1822 ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n",
1823 ipv6_hdr(skb)->hop_limit);
1824 return 0;
1825 }
1826
1827 if (msg->icmph.icmp6_code != 0) {
1828 ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n",
1829 msg->icmph.icmp6_code);
1830 return 0;
1831 }
1832
1833 switch (msg->icmph.icmp6_type) {
1834 case NDISC_NEIGHBOUR_SOLICITATION:
1835 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1836 ndisc_recv_ns(skb);
1837 break;
1838
1839 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1840 ndisc_recv_na(skb);
1841 break;
1842
1843 case NDISC_ROUTER_SOLICITATION:
1844 ndisc_recv_rs(skb);
1845 break;
1846
1847 case NDISC_ROUTER_ADVERTISEMENT:
1848 ndisc_router_discovery(skb);
1849 break;
1850
1851 case NDISC_REDIRECT:
1852 ndisc_redirect_rcv(skb);
1853 break;
1854 }
1855
1856 return 0;
1857}
1858
1859static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1860{
1861 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1862 struct netdev_notifier_change_info *change_info;
1863 struct net *net = dev_net(dev);
1864 struct inet6_dev *idev;
1865 bool evict_nocarrier;
1866
1867 switch (event) {
1868 case NETDEV_CHANGEADDR:
1869 neigh_changeaddr(&nd_tbl, dev);
1870 fib6_run_gc(0, net, false);
1871 fallthrough;
1872 case NETDEV_UP:
1873 idev = in6_dev_get(dev);
1874 if (!idev)
1875 break;
1876 if (idev->cnf.ndisc_notify ||
1877 net->ipv6.devconf_all->ndisc_notify)
1878 ndisc_send_unsol_na(dev);
1879 in6_dev_put(idev);
1880 break;
1881 case NETDEV_CHANGE:
1882 idev = in6_dev_get(dev);
1883 if (!idev)
1884 evict_nocarrier = true;
1885 else {
1886 evict_nocarrier = idev->cnf.ndisc_evict_nocarrier &&
1887 net->ipv6.devconf_all->ndisc_evict_nocarrier;
1888 in6_dev_put(idev);
1889 }
1890
1891 change_info = ptr;
1892 if (change_info->flags_changed & IFF_NOARP)
1893 neigh_changeaddr(&nd_tbl, dev);
1894 if (evict_nocarrier && !netif_carrier_ok(dev))
1895 neigh_carrier_down(&nd_tbl, dev);
1896 break;
1897 case NETDEV_DOWN:
1898 neigh_ifdown(&nd_tbl, dev);
1899 fib6_run_gc(0, net, false);
1900 break;
1901 case NETDEV_NOTIFY_PEERS:
1902 ndisc_send_unsol_na(dev);
1903 break;
1904 default:
1905 break;
1906 }
1907
1908 return NOTIFY_DONE;
1909}
1910
1911static struct notifier_block ndisc_netdev_notifier = {
1912 .notifier_call = ndisc_netdev_event,
1913 .priority = ADDRCONF_NOTIFY_PRIORITY - 5,
1914};
1915
1916#ifdef CONFIG_SYSCTL
1917static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
1918 const char *func, const char *dev_name)
1919{
1920 static char warncomm[TASK_COMM_LEN];
1921 static int warned;
1922 if (strcmp(warncomm, current->comm) && warned < 5) {
1923 strcpy(warncomm, current->comm);
1924 pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n",
1925 warncomm, func,
1926 dev_name, ctl->procname,
1927 dev_name, ctl->procname);
1928 warned++;
1929 }
1930}
1931
1932int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void *buffer,
1933 size_t *lenp, loff_t *ppos)
1934{
1935 struct net_device *dev = ctl->extra1;
1936 struct inet6_dev *idev;
1937 int ret;
1938
1939 if ((strcmp(ctl->procname, "retrans_time") == 0) ||
1940 (strcmp(ctl->procname, "base_reachable_time") == 0))
1941 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1942
1943 if (strcmp(ctl->procname, "retrans_time") == 0)
1944 ret = neigh_proc_dointvec(ctl, write, buffer, lenp, ppos);
1945
1946 else if (strcmp(ctl->procname, "base_reachable_time") == 0)
1947 ret = neigh_proc_dointvec_jiffies(ctl, write,
1948 buffer, lenp, ppos);
1949
1950 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
1951 (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
1952 ret = neigh_proc_dointvec_ms_jiffies(ctl, write,
1953 buffer, lenp, ppos);
1954 else
1955 ret = -1;
1956
1957 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1958 if (ctl->data == &NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME))
1959 idev->nd_parms->reachable_time =
1960 neigh_rand_reach_time(NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME));
1961 idev->tstamp = jiffies;
1962 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1963 in6_dev_put(idev);
1964 }
1965 return ret;
1966}
1967
1968
1969#endif
1970
1971static int __net_init ndisc_net_init(struct net *net)
1972{
1973 struct ipv6_pinfo *np;
1974 struct sock *sk;
1975 int err;
1976
1977 err = inet_ctl_sock_create(&sk, PF_INET6,
1978 SOCK_RAW, IPPROTO_ICMPV6, net);
1979 if (err < 0) {
1980 ND_PRINTK(0, err,
1981 "NDISC: Failed to initialize the control socket (err %d)\n",
1982 err);
1983 return err;
1984 }
1985
1986 net->ipv6.ndisc_sk = sk;
1987
1988 np = inet6_sk(sk);
1989 np->hop_limit = 255;
1990 /* Do not loopback ndisc messages */
1991 np->mc_loop = 0;
1992
1993 return 0;
1994}
1995
1996static void __net_exit ndisc_net_exit(struct net *net)
1997{
1998 inet_ctl_sock_destroy(net->ipv6.ndisc_sk);
1999}
2000
2001static struct pernet_operations ndisc_net_ops = {
2002 .init = ndisc_net_init,
2003 .exit = ndisc_net_exit,
2004};
2005
2006int __init ndisc_init(void)
2007{
2008 int err;
2009
2010 err = register_pernet_subsys(&ndisc_net_ops);
2011 if (err)
2012 return err;
2013 /*
2014 * Initialize the neighbour table
2015 */
2016 neigh_table_init(NEIGH_ND_TABLE, &nd_tbl);
2017
2018#ifdef CONFIG_SYSCTL
2019 err = neigh_sysctl_register(NULL, &nd_tbl.parms,
2020 ndisc_ifinfo_sysctl_change);
2021 if (err)
2022 goto out_unregister_pernet;
2023out:
2024#endif
2025 return err;
2026
2027#ifdef CONFIG_SYSCTL
2028out_unregister_pernet:
2029 unregister_pernet_subsys(&ndisc_net_ops);
2030 goto out;
2031#endif
2032}
2033
2034int __init ndisc_late_init(void)
2035{
2036 return register_netdevice_notifier(&ndisc_netdev_notifier);
2037}
2038
2039void ndisc_late_cleanup(void)
2040{
2041 unregister_netdevice_notifier(&ndisc_netdev_notifier);
2042}
2043
2044void ndisc_cleanup(void)
2045{
2046#ifdef CONFIG_SYSCTL
2047 neigh_sysctl_unregister(&nd_tbl.parms);
2048#endif
2049 neigh_table_clear(NEIGH_ND_TABLE, &nd_tbl);
2050 unregister_pernet_subsys(&ndisc_net_ops);
2051}