2 * Neighbour Discovery for IPv6
3 * Linux INET6 implementation
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Mike Shaver <shaver@ingenia.com>
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.
18 * Pierre Ynard : export userland ND options
19 * through netlink (RDNSS support)
20 * Lars Fenneberg : fixed MTU setting on receipt
22 * Janos Farkas : kmalloc failure checks
23 * Alexey Kuznetsov : state machine reworked
24 * and moved to net/core.
25 * Pekka Savola : RFC2461 validation
26 * YOSHIFUJI Hideaki @USAGI : Verify ND options properly
29 /* Set to 3 to get tracing... */
32 #define ND_PRINTK(fmt, args...) do { if (net_ratelimit()) { printk(fmt, ## args); } } while(0)
33 #define ND_NOPRINTK(x...) do { ; } while(0)
34 #define ND_PRINTK0 ND_PRINTK
35 #define ND_PRINTK1 ND_NOPRINTK
36 #define ND_PRINTK2 ND_NOPRINTK
37 #define ND_PRINTK3 ND_NOPRINTK
40 #define ND_PRINTK1 ND_PRINTK
44 #define ND_PRINTK2 ND_PRINTK
48 #define ND_PRINTK3 ND_PRINTK
51 #include <linux/module.h>
52 #include <linux/errno.h>
53 #include <linux/types.h>
54 #include <linux/socket.h>
55 #include <linux/sockios.h>
56 #include <linux/sched.h>
57 #include <linux/net.h>
58 #include <linux/in6.h>
59 #include <linux/route.h>
60 #include <linux/init.h>
61 #include <linux/rcupdate.h>
62 #include <linux/slab.h>
64 #include <linux/sysctl.h>
67 #include <linux/if_addr.h>
68 #include <linux/if_arp.h>
69 #include <linux/ipv6.h>
70 #include <linux/icmpv6.h>
71 #include <linux/jhash.h>
77 #include <net/protocol.h>
78 #include <net/ndisc.h>
79 #include <net/ip6_route.h>
80 #include <net/addrconf.h>
83 #include <net/netlink.h>
84 #include <linux/rtnetlink.h>
87 #include <net/ip6_checksum.h>
88 #include <net/inet_common.h>
89 #include <linux/proc_fs.h>
91 #include <linux/netfilter.h>
92 #include <linux/netfilter_ipv6.h>
94 static u32 ndisc_hash(const void *pkey,
95 const struct net_device *dev,
97 static int ndisc_constructor(struct neighbour *neigh);
98 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
99 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
100 static int pndisc_constructor(struct pneigh_entry *n);
101 static void pndisc_destructor(struct pneigh_entry *n);
102 static void pndisc_redo(struct sk_buff *skb);
104 static const struct neigh_ops ndisc_generic_ops = {
106 .solicit = ndisc_solicit,
107 .error_report = ndisc_error_report,
108 .output = neigh_resolve_output,
109 .connected_output = neigh_connected_output,
112 static const struct neigh_ops ndisc_hh_ops = {
114 .solicit = ndisc_solicit,
115 .error_report = ndisc_error_report,
116 .output = neigh_resolve_output,
117 .connected_output = neigh_resolve_output,
121 static const struct neigh_ops ndisc_direct_ops = {
123 .output = neigh_direct_output,
124 .connected_output = neigh_direct_output,
127 struct neigh_table nd_tbl = {
129 .key_len = sizeof(struct in6_addr),
131 .constructor = ndisc_constructor,
132 .pconstructor = pndisc_constructor,
133 .pdestructor = pndisc_destructor,
134 .proxy_redo = pndisc_redo,
138 .base_reachable_time = ND_REACHABLE_TIME,
139 .retrans_time = ND_RETRANS_TIMER,
140 .gc_staletime = 60 * HZ,
141 .reachable_time = ND_REACHABLE_TIME,
142 .delay_probe_time = 5 * HZ,
143 .queue_len_bytes = 64*1024,
146 .anycast_delay = 1 * HZ,
147 .proxy_delay = (8 * HZ) / 10,
150 .gc_interval = 30 * HZ,
157 struct ndisc_options {
158 struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX];
159 #ifdef CONFIG_IPV6_ROUTE_INFO
160 struct nd_opt_hdr *nd_opts_ri;
161 struct nd_opt_hdr *nd_opts_ri_end;
163 struct nd_opt_hdr *nd_useropts;
164 struct nd_opt_hdr *nd_useropts_end;
167 #define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
168 #define nd_opts_tgt_lladdr nd_opt_array[ND_OPT_TARGET_LL_ADDR]
169 #define nd_opts_pi nd_opt_array[ND_OPT_PREFIX_INFO]
170 #define nd_opts_pi_end nd_opt_array[__ND_OPT_PREFIX_INFO_END]
171 #define nd_opts_rh nd_opt_array[ND_OPT_REDIRECT_HDR]
172 #define nd_opts_mtu nd_opt_array[ND_OPT_MTU]
174 #define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
177 * Return the padding between the option length and the start of the
178 * link addr. Currently only IP-over-InfiniBand needs this, although
179 * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
180 * also need a pad of 2.
182 static int ndisc_addr_option_pad(unsigned short type)
185 case ARPHRD_INFINIBAND: return 2;
190 static inline int ndisc_opt_addr_space(struct net_device *dev)
192 return NDISC_OPT_SPACE(dev->addr_len + ndisc_addr_option_pad(dev->type));
195 static u8 *ndisc_fill_addr_option(u8 *opt, int type, void *data, int data_len,
196 unsigned short addr_type)
198 int space = NDISC_OPT_SPACE(data_len);
199 int pad = ndisc_addr_option_pad(addr_type);
204 memset(opt + 2, 0, pad);
208 memcpy(opt+2, data, data_len);
211 if ((space -= data_len) > 0)
212 memset(opt, 0, space);
216 static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur,
217 struct nd_opt_hdr *end)
220 if (!cur || !end || cur >= end)
222 type = cur->nd_opt_type;
224 cur = ((void *)cur) + (cur->nd_opt_len << 3);
225 } while(cur < end && cur->nd_opt_type != type);
226 return cur <= end && cur->nd_opt_type == type ? cur : NULL;
229 static inline int ndisc_is_useropt(struct nd_opt_hdr *opt)
231 return opt->nd_opt_type == ND_OPT_RDNSS;
234 static struct nd_opt_hdr *ndisc_next_useropt(struct nd_opt_hdr *cur,
235 struct nd_opt_hdr *end)
237 if (!cur || !end || cur >= end)
240 cur = ((void *)cur) + (cur->nd_opt_len << 3);
241 } while(cur < end && !ndisc_is_useropt(cur));
242 return cur <= end && ndisc_is_useropt(cur) ? cur : NULL;
245 static struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len,
246 struct ndisc_options *ndopts)
248 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
250 if (!nd_opt || opt_len < 0 || !ndopts)
252 memset(ndopts, 0, sizeof(*ndopts));
255 if (opt_len < sizeof(struct nd_opt_hdr))
257 l = nd_opt->nd_opt_len << 3;
258 if (opt_len < l || l == 0)
260 switch (nd_opt->nd_opt_type) {
261 case ND_OPT_SOURCE_LL_ADDR:
262 case ND_OPT_TARGET_LL_ADDR:
264 case ND_OPT_REDIRECT_HDR:
265 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
266 ND_PRINTK2(KERN_WARNING
267 "%s(): duplicated ND6 option found: type=%d\n",
269 nd_opt->nd_opt_type);
271 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
274 case ND_OPT_PREFIX_INFO:
275 ndopts->nd_opts_pi_end = nd_opt;
276 if (!ndopts->nd_opt_array[nd_opt->nd_opt_type])
277 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
279 #ifdef CONFIG_IPV6_ROUTE_INFO
280 case ND_OPT_ROUTE_INFO:
281 ndopts->nd_opts_ri_end = nd_opt;
282 if (!ndopts->nd_opts_ri)
283 ndopts->nd_opts_ri = nd_opt;
287 if (ndisc_is_useropt(nd_opt)) {
288 ndopts->nd_useropts_end = nd_opt;
289 if (!ndopts->nd_useropts)
290 ndopts->nd_useropts = nd_opt;
293 * Unknown options must be silently ignored,
294 * to accommodate future extension to the
297 ND_PRINTK2(KERN_NOTICE
298 "%s(): ignored unsupported option; type=%d, len=%d\n",
300 nd_opt->nd_opt_type, nd_opt->nd_opt_len);
304 nd_opt = ((void *)nd_opt) + l;
309 static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
310 struct net_device *dev)
312 u8 *lladdr = (u8 *)(p + 1);
313 int lladdrlen = p->nd_opt_len << 3;
314 int prepad = ndisc_addr_option_pad(dev->type);
315 if (lladdrlen != NDISC_OPT_SPACE(dev->addr_len + prepad))
317 return lladdr + prepad;
320 int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
324 case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */
326 ipv6_eth_mc_map(addr, buf);
328 case ARPHRD_IEEE802_TR:
329 ipv6_tr_mc_map(addr,buf);
332 ipv6_arcnet_mc_map(addr, buf);
334 case ARPHRD_INFINIBAND:
335 ipv6_ib_mc_map(addr, dev->broadcast, buf);
338 return ipv6_ipgre_mc_map(addr, dev->broadcast, buf);
341 memcpy(buf, dev->broadcast, dev->addr_len);
348 EXPORT_SYMBOL(ndisc_mc_map);
350 static u32 ndisc_hash(const void *pkey,
351 const struct net_device *dev,
354 const u32 *p32 = pkey;
358 for (i = 0; i < (sizeof(struct in6_addr) / sizeof(u32)); i++)
361 return jhash_2words(addr_hash, dev->ifindex, hash_rnd);
364 static int ndisc_constructor(struct neighbour *neigh)
366 struct in6_addr *addr = (struct in6_addr*)&neigh->primary_key;
367 struct net_device *dev = neigh->dev;
368 struct inet6_dev *in6_dev;
369 struct neigh_parms *parms;
370 int is_multicast = ipv6_addr_is_multicast(addr);
372 in6_dev = in6_dev_get(dev);
373 if (in6_dev == NULL) {
377 parms = in6_dev->nd_parms;
378 __neigh_parms_put(neigh->parms);
379 neigh->parms = neigh_parms_clone(parms);
381 neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
382 if (!dev->header_ops) {
383 neigh->nud_state = NUD_NOARP;
384 neigh->ops = &ndisc_direct_ops;
385 neigh->output = neigh_direct_output;
388 neigh->nud_state = NUD_NOARP;
389 ndisc_mc_map(addr, neigh->ha, dev, 1);
390 } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
391 neigh->nud_state = NUD_NOARP;
392 memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
393 if (dev->flags&IFF_LOOPBACK)
394 neigh->type = RTN_LOCAL;
395 } else if (dev->flags&IFF_POINTOPOINT) {
396 neigh->nud_state = NUD_NOARP;
397 memcpy(neigh->ha, dev->broadcast, dev->addr_len);
399 if (dev->header_ops->cache)
400 neigh->ops = &ndisc_hh_ops;
402 neigh->ops = &ndisc_generic_ops;
403 if (neigh->nud_state&NUD_VALID)
404 neigh->output = neigh->ops->connected_output;
406 neigh->output = neigh->ops->output;
408 in6_dev_put(in6_dev);
412 static int pndisc_constructor(struct pneigh_entry *n)
414 struct in6_addr *addr = (struct in6_addr*)&n->key;
415 struct in6_addr maddr;
416 struct net_device *dev = n->dev;
418 if (dev == NULL || __in6_dev_get(dev) == NULL)
420 addrconf_addr_solict_mult(addr, &maddr);
421 ipv6_dev_mc_inc(dev, &maddr);
425 static void pndisc_destructor(struct pneigh_entry *n)
427 struct in6_addr *addr = (struct in6_addr*)&n->key;
428 struct in6_addr maddr;
429 struct net_device *dev = n->dev;
431 if (dev == NULL || __in6_dev_get(dev) == NULL)
433 addrconf_addr_solict_mult(addr, &maddr);
434 ipv6_dev_mc_dec(dev, &maddr);
437 struct sk_buff *ndisc_build_skb(struct net_device *dev,
438 const struct in6_addr *daddr,
439 const struct in6_addr *saddr,
440 struct icmp6hdr *icmp6h,
441 const struct in6_addr *target,
444 struct net *net = dev_net(dev);
445 struct sock *sk = net->ipv6.ndisc_sk;
447 struct icmp6hdr *hdr;
448 int hlen = LL_RESERVED_SPACE(dev);
449 int tlen = dev->needed_tailroom;
457 len = sizeof(struct icmp6hdr) + (target ? sizeof(*target) : 0);
459 len += ndisc_opt_addr_space(dev);
461 skb = sock_alloc_send_skb(sk,
462 (MAX_HEADER + sizeof(struct ipv6hdr) +
467 "ICMPv6 ND: %s() failed to allocate an skb, err=%d.\n",
472 skb_reserve(skb, hlen);
473 ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
475 skb->transport_header = skb->tail;
478 hdr = (struct icmp6hdr *)skb_transport_header(skb);
479 memcpy(hdr, icmp6h, sizeof(*hdr));
481 opt = skb_transport_header(skb) + sizeof(struct icmp6hdr);
483 *(struct in6_addr *)opt = *target;
484 opt += sizeof(*target);
488 ndisc_fill_addr_option(opt, llinfo, dev->dev_addr,
489 dev->addr_len, dev->type);
491 hdr->icmp6_cksum = csum_ipv6_magic(saddr, daddr, len,
499 EXPORT_SYMBOL(ndisc_build_skb);
501 void ndisc_send_skb(struct sk_buff *skb,
502 struct net_device *dev,
503 struct neighbour *neigh,
504 const struct in6_addr *daddr,
505 const struct in6_addr *saddr,
506 struct icmp6hdr *icmp6h)
509 struct dst_entry *dst;
510 struct net *net = dev_net(dev);
511 struct sock *sk = net->ipv6.ndisc_sk;
512 struct inet6_dev *idev;
516 type = icmp6h->icmp6_type;
518 icmpv6_flow_init(sk, &fl6, type, saddr, daddr, dev->ifindex);
519 dst = icmp6_dst_alloc(dev, neigh, &fl6);
525 skb_dst_set(skb, dst);
528 idev = __in6_dev_get(dst->dev);
529 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
531 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL, dst->dev,
534 ICMP6MSGOUT_INC_STATS(net, idev, type);
535 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
541 EXPORT_SYMBOL(ndisc_send_skb);
544 * Send a Neighbour Discover packet
546 static void __ndisc_send(struct net_device *dev,
547 struct neighbour *neigh,
548 const struct in6_addr *daddr,
549 const struct in6_addr *saddr,
550 struct icmp6hdr *icmp6h, const struct in6_addr *target,
555 skb = ndisc_build_skb(dev, daddr, saddr, icmp6h, target, llinfo);
559 ndisc_send_skb(skb, dev, neigh, daddr, saddr, icmp6h);
562 static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
563 const struct in6_addr *daddr,
564 const struct in6_addr *solicited_addr,
565 int router, int solicited, int override, int inc_opt)
567 struct in6_addr tmpaddr;
568 struct inet6_ifaddr *ifp;
569 const struct in6_addr *src_addr;
570 struct icmp6hdr icmp6h = {
571 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
574 /* for anycast or proxy, solicited_addr != src_addr */
575 ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1);
577 src_addr = solicited_addr;
578 if (ifp->flags & IFA_F_OPTIMISTIC)
580 inc_opt |= ifp->idev->cnf.force_tllao;
583 if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr,
584 inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs,
590 icmp6h.icmp6_router = router;
591 icmp6h.icmp6_solicited = solicited;
592 icmp6h.icmp6_override = override;
594 __ndisc_send(dev, neigh, daddr, src_addr,
595 &icmp6h, solicited_addr,
596 inc_opt ? ND_OPT_TARGET_LL_ADDR : 0);
599 static void ndisc_send_unsol_na(struct net_device *dev)
601 struct inet6_dev *idev;
602 struct inet6_ifaddr *ifa;
603 struct in6_addr mcaddr;
605 idev = in6_dev_get(dev);
609 read_lock_bh(&idev->lock);
610 list_for_each_entry(ifa, &idev->addr_list, if_list) {
611 addrconf_addr_solict_mult(&ifa->addr, &mcaddr);
612 ndisc_send_na(dev, NULL, &mcaddr, &ifa->addr,
613 /*router=*/ !!idev->cnf.forwarding,
614 /*solicited=*/ false, /*override=*/ true,
617 read_unlock_bh(&idev->lock);
622 void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh,
623 const struct in6_addr *solicit,
624 const struct in6_addr *daddr, const struct in6_addr *saddr)
626 struct in6_addr addr_buf;
627 struct icmp6hdr icmp6h = {
628 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
632 if (ipv6_get_lladdr(dev, &addr_buf,
633 (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
638 __ndisc_send(dev, neigh, daddr, saddr,
640 !ipv6_addr_any(saddr) ? ND_OPT_SOURCE_LL_ADDR : 0);
643 void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr,
644 const struct in6_addr *daddr)
646 struct icmp6hdr icmp6h = {
647 .icmp6_type = NDISC_ROUTER_SOLICITATION,
649 int send_sllao = dev->addr_len;
651 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
653 * According to section 2.2 of RFC 4429, we must not
654 * send router solicitations with a sllao from
655 * optimistic addresses, but we may send the solicitation
656 * if we don't include the sllao. So here we check
657 * if our address is optimistic, and if so, we
658 * suppress the inclusion of the sllao.
661 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr,
664 if (ifp->flags & IFA_F_OPTIMISTIC) {
673 __ndisc_send(dev, NULL, daddr, saddr,
675 send_sllao ? ND_OPT_SOURCE_LL_ADDR : 0);
679 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
682 * "The sender MUST return an ICMP
683 * destination unreachable"
685 dst_link_failure(skb);
689 /* Called with locked neigh: either read or both */
691 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
693 struct in6_addr *saddr = NULL;
694 struct in6_addr mcaddr;
695 struct net_device *dev = neigh->dev;
696 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
697 int probes = atomic_read(&neigh->probes);
699 if (skb && ipv6_chk_addr(dev_net(dev), &ipv6_hdr(skb)->saddr, dev, 1))
700 saddr = &ipv6_hdr(skb)->saddr;
702 if ((probes -= neigh->parms->ucast_probes) < 0) {
703 if (!(neigh->nud_state & NUD_VALID)) {
704 ND_PRINTK1(KERN_DEBUG "%s(): trying to ucast probe in NUD_INVALID: %pI6\n",
707 ndisc_send_ns(dev, neigh, target, target, saddr);
708 } else if ((probes -= neigh->parms->app_probes) < 0) {
713 addrconf_addr_solict_mult(target, &mcaddr);
714 ndisc_send_ns(dev, NULL, target, &mcaddr, saddr);
718 static int pndisc_is_router(const void *pkey,
719 struct net_device *dev)
721 struct pneigh_entry *n;
724 read_lock_bh(&nd_tbl.lock);
725 n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev);
727 ret = !!(n->flags & NTF_ROUTER);
728 read_unlock_bh(&nd_tbl.lock);
733 static void ndisc_recv_ns(struct sk_buff *skb)
735 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
736 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
737 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
739 u32 ndoptlen = skb->tail - (skb->transport_header +
740 offsetof(struct nd_msg, opt));
741 struct ndisc_options ndopts;
742 struct net_device *dev = skb->dev;
743 struct inet6_ifaddr *ifp;
744 struct inet6_dev *idev = NULL;
745 struct neighbour *neigh;
746 int dad = ipv6_addr_any(saddr);
750 if (ipv6_addr_is_multicast(&msg->target)) {
751 ND_PRINTK2(KERN_WARNING
752 "ICMPv6 NS: multicast target address");
758 * DAD has to be destined for solicited node multicast address.
761 !(daddr->s6_addr32[0] == htonl(0xff020000) &&
762 daddr->s6_addr32[1] == htonl(0x00000000) &&
763 daddr->s6_addr32[2] == htonl(0x00000001) &&
764 daddr->s6_addr [12] == 0xff )) {
765 ND_PRINTK2(KERN_WARNING
766 "ICMPv6 NS: bad DAD packet (wrong destination)\n");
770 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
771 ND_PRINTK2(KERN_WARNING
772 "ICMPv6 NS: invalid ND options\n");
776 if (ndopts.nd_opts_src_lladdr) {
777 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
779 ND_PRINTK2(KERN_WARNING
780 "ICMPv6 NS: invalid link-layer address length\n");
785 * If the IP source address is the unspecified address,
786 * there MUST NOT be source link-layer address option
790 ND_PRINTK2(KERN_WARNING
791 "ICMPv6 NS: bad DAD packet (link-layer address option)\n");
796 inc = ipv6_addr_is_multicast(daddr);
798 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
801 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
803 if (dev->type == ARPHRD_IEEE802_TR) {
804 const unsigned char *sadr;
805 sadr = skb_mac_header(skb);
806 if (((sadr[8] ^ dev->dev_addr[0]) & 0x7f) == 0 &&
807 sadr[9] == dev->dev_addr[1] &&
808 sadr[10] == dev->dev_addr[2] &&
809 sadr[11] == dev->dev_addr[3] &&
810 sadr[12] == dev->dev_addr[4] &&
811 sadr[13] == dev->dev_addr[5]) {
812 /* looped-back to us */
818 * We are colliding with another node
820 * so fail our DAD process
822 addrconf_dad_failure(ifp);
826 * This is not a dad solicitation.
827 * If we are an optimistic node,
829 * Otherwise, we should ignore it.
831 if (!(ifp->flags & IFA_F_OPTIMISTIC))
838 struct net *net = dev_net(dev);
840 idev = in6_dev_get(dev);
842 /* XXX: count this drop? */
846 if (ipv6_chk_acast_addr(net, dev, &msg->target) ||
847 (idev->cnf.forwarding &&
848 (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) &&
849 (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) {
850 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
851 skb->pkt_type != PACKET_HOST &&
853 idev->nd_parms->proxy_delay != 0) {
855 * for anycast or proxy,
856 * sender should delay its response
857 * by a random time between 0 and
858 * MAX_ANYCAST_DELAY_TIME seconds.
859 * (RFC2461) -- yoshfuji
861 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
863 pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
871 is_router = !!idev->cnf.forwarding;
874 ndisc_send_na(dev, NULL, &in6addr_linklocal_allnodes, &msg->target,
875 is_router, 0, (ifp != NULL), 1);
880 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
882 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
885 * update / create cache entry
886 * for the source address
888 neigh = __neigh_lookup(&nd_tbl, saddr, dev,
889 !inc || lladdr || !dev->addr_len);
891 neigh_update(neigh, lladdr, NUD_STALE,
892 NEIGH_UPDATE_F_WEAK_OVERRIDE|
893 NEIGH_UPDATE_F_OVERRIDE);
894 if (neigh || !dev->header_ops) {
895 ndisc_send_na(dev, neigh, saddr, &msg->target,
897 1, (ifp != NULL && inc), inc);
899 neigh_release(neigh);
909 static void ndisc_recv_na(struct sk_buff *skb)
911 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
912 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
913 const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
915 u32 ndoptlen = skb->tail - (skb->transport_header +
916 offsetof(struct nd_msg, opt));
917 struct ndisc_options ndopts;
918 struct net_device *dev = skb->dev;
919 struct inet6_ifaddr *ifp;
920 struct neighbour *neigh;
922 if (skb->len < sizeof(struct nd_msg)) {
923 ND_PRINTK2(KERN_WARNING
924 "ICMPv6 NA: packet too short\n");
928 if (ipv6_addr_is_multicast(&msg->target)) {
929 ND_PRINTK2(KERN_WARNING
930 "ICMPv6 NA: target address is multicast.\n");
934 if (ipv6_addr_is_multicast(daddr) &&
935 msg->icmph.icmp6_solicited) {
936 ND_PRINTK2(KERN_WARNING
937 "ICMPv6 NA: solicited NA is multicasted.\n");
941 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
942 ND_PRINTK2(KERN_WARNING
943 "ICMPv6 NS: invalid ND option\n");
946 if (ndopts.nd_opts_tgt_lladdr) {
947 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
949 ND_PRINTK2(KERN_WARNING
950 "ICMPv6 NA: invalid link-layer address length\n");
954 ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
956 if (skb->pkt_type != PACKET_LOOPBACK
957 && (ifp->flags & IFA_F_TENTATIVE)) {
958 addrconf_dad_failure(ifp);
961 /* What should we make now? The advertisement
962 is invalid, but ndisc specs say nothing
963 about it. It could be misconfiguration, or
964 an smart proxy agent tries to help us :-)
966 We should not print the error if NA has been
967 received from loopback - it is just our own
968 unsolicited advertisement.
970 if (skb->pkt_type != PACKET_LOOPBACK)
971 ND_PRINTK1(KERN_WARNING
972 "ICMPv6 NA: someone advertises our address %pI6 on %s!\n",
973 &ifp->addr, ifp->idev->dev->name);
977 neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
980 u8 old_flags = neigh->flags;
981 struct net *net = dev_net(dev);
983 if (neigh->nud_state & NUD_FAILED)
987 * Don't update the neighbor cache entry on a proxy NA from
988 * ourselves because either the proxied node is off link or it
989 * has already sent a NA to us.
991 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
992 net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp &&
993 pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) {
994 /* XXX: idev->cnf.prixy_ndp */
998 neigh_update(neigh, lladdr,
999 msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
1000 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1001 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
1002 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1003 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0));
1005 if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
1007 * Change: router to host
1009 struct rt6_info *rt;
1010 rt = rt6_get_dflt_router(saddr, dev);
1016 neigh_release(neigh);
1020 static void ndisc_recv_rs(struct sk_buff *skb)
1022 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
1023 unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
1024 struct neighbour *neigh;
1025 struct inet6_dev *idev;
1026 const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
1027 struct ndisc_options ndopts;
1030 if (skb->len < sizeof(*rs_msg))
1033 idev = __in6_dev_get(skb->dev);
1035 if (net_ratelimit())
1036 ND_PRINTK1("ICMP6 RS: can't find in6 device\n");
1040 /* Don't accept RS if we're not in router mode */
1041 if (!idev->cnf.forwarding)
1045 * Don't update NCE if src = ::;
1046 * this implies that the source node has no ip address assigned yet.
1048 if (ipv6_addr_any(saddr))
1051 /* Parse ND options */
1052 if (!ndisc_parse_options(rs_msg->opt, ndoptlen, &ndopts)) {
1053 if (net_ratelimit())
1054 ND_PRINTK2("ICMP6 NS: invalid ND option, ignored\n");
1058 if (ndopts.nd_opts_src_lladdr) {
1059 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1065 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
1067 neigh_update(neigh, lladdr, NUD_STALE,
1068 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1069 NEIGH_UPDATE_F_OVERRIDE|
1070 NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
1071 neigh_release(neigh);
1077 static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
1079 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
1080 struct sk_buff *skb;
1081 struct nlmsghdr *nlh;
1082 struct nduseroptmsg *ndmsg;
1083 struct net *net = dev_net(ra->dev);
1085 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
1086 + (opt->nd_opt_len << 3));
1087 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
1089 skb = nlmsg_new(msg_size, GFP_ATOMIC);
1095 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
1097 goto nla_put_failure;
1100 ndmsg = nlmsg_data(nlh);
1101 ndmsg->nduseropt_family = AF_INET6;
1102 ndmsg->nduseropt_ifindex = ra->dev->ifindex;
1103 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
1104 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
1105 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
1107 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
1109 NLA_PUT(skb, NDUSEROPT_SRCADDR, sizeof(struct in6_addr),
1110 &ipv6_hdr(ra)->saddr);
1111 nlmsg_end(skb, nlh);
1113 rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC);
1120 rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err);
1123 static inline int accept_ra(struct inet6_dev *in6_dev)
1126 * If forwarding is enabled, RA are not accepted unless the special
1127 * hybrid mode (accept_ra=2) is enabled.
1129 if (in6_dev->cnf.forwarding && in6_dev->cnf.accept_ra < 2)
1132 return in6_dev->cnf.accept_ra;
1135 static void ndisc_router_discovery(struct sk_buff *skb)
1137 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
1138 struct neighbour *neigh = NULL;
1139 struct inet6_dev *in6_dev;
1140 struct rt6_info *rt = NULL;
1142 struct ndisc_options ndopts;
1144 unsigned int pref = 0;
1146 __u8 * opt = (__u8 *)(ra_msg + 1);
1148 optlen = (skb->tail - skb->transport_header) - sizeof(struct ra_msg);
1150 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1151 ND_PRINTK2(KERN_WARNING
1152 "ICMPv6 RA: source address is not link-local.\n");
1156 ND_PRINTK2(KERN_WARNING
1157 "ICMPv6 RA: packet too short\n");
1161 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1162 if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) {
1163 ND_PRINTK2(KERN_WARNING
1164 "ICMPv6 RA: from host or unauthorized router\n");
1170 * set the RA_RECV flag in the interface
1173 in6_dev = __in6_dev_get(skb->dev);
1174 if (in6_dev == NULL) {
1176 "ICMPv6 RA: can't find inet6 device for %s.\n",
1181 if (!ndisc_parse_options(opt, optlen, &ndopts)) {
1182 ND_PRINTK2(KERN_WARNING
1183 "ICMP6 RA: invalid ND options\n");
1187 if (!accept_ra(in6_dev))
1188 goto skip_linkparms;
1190 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1191 /* skip link-specific parameters from interior routers */
1192 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT)
1193 goto skip_linkparms;
1196 if (in6_dev->if_flags & IF_RS_SENT) {
1198 * flag that an RA was received after an RS was sent
1199 * out on this interface.
1201 in6_dev->if_flags |= IF_RA_RCVD;
1205 * Remember the managed/otherconf flags from most recently
1206 * received RA message (RFC 2462) -- yoshfuji
1208 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1210 (ra_msg->icmph.icmp6_addrconf_managed ?
1211 IF_RA_MANAGED : 0) |
1212 (ra_msg->icmph.icmp6_addrconf_other ?
1213 IF_RA_OTHERCONF : 0);
1215 if (!in6_dev->cnf.accept_ra_defrtr)
1218 if (ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, NULL, 0))
1221 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1223 #ifdef CONFIG_IPV6_ROUTER_PREF
1224 pref = ra_msg->icmph.icmp6_router_pref;
1225 /* 10b is handled as if it were 00b (medium) */
1226 if (pref == ICMPV6_ROUTER_PREF_INVALID ||
1227 !in6_dev->cnf.accept_ra_rtr_pref)
1228 pref = ICMPV6_ROUTER_PREF_MEDIUM;
1231 rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev);
1234 neigh = dst_get_neighbour_noref(&rt->dst);
1236 if (rt && lifetime == 0) {
1242 if (rt == NULL && lifetime) {
1243 ND_PRINTK3(KERN_DEBUG
1244 "ICMPv6 RA: adding default router.\n");
1246 rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref);
1249 "ICMPv6 RA: %s() failed to add default route.\n",
1254 neigh = dst_get_neighbour_noref(&rt->dst);
1255 if (neigh == NULL) {
1257 "ICMPv6 RA: %s() got default router without neighbour.\n",
1259 dst_release(&rt->dst);
1262 neigh->flags |= NTF_ROUTER;
1264 rt->rt6i_flags = (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
1268 rt->rt6i_expires = jiffies + (HZ * lifetime);
1270 if (ra_msg->icmph.icmp6_hop_limit) {
1271 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
1273 dst_metric_set(&rt->dst, RTAX_HOPLIMIT,
1274 ra_msg->icmph.icmp6_hop_limit);
1280 * Update Reachable Time and Retrans Timer
1283 if (in6_dev->nd_parms) {
1284 unsigned long rtime = ntohl(ra_msg->retrans_timer);
1286 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1287 rtime = (rtime*HZ)/1000;
1290 in6_dev->nd_parms->retrans_time = rtime;
1291 in6_dev->tstamp = jiffies;
1292 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1295 rtime = ntohl(ra_msg->reachable_time);
1296 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1297 rtime = (rtime*HZ)/1000;
1302 if (rtime != in6_dev->nd_parms->base_reachable_time) {
1303 in6_dev->nd_parms->base_reachable_time = rtime;
1304 in6_dev->nd_parms->gc_staletime = 3 * rtime;
1305 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1306 in6_dev->tstamp = jiffies;
1307 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1319 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
1323 if (ndopts.nd_opts_src_lladdr) {
1324 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1327 ND_PRINTK2(KERN_WARNING
1328 "ICMPv6 RA: invalid link-layer address length\n");
1332 neigh_update(neigh, lladdr, NUD_STALE,
1333 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1334 NEIGH_UPDATE_F_OVERRIDE|
1335 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1336 NEIGH_UPDATE_F_ISROUTER);
1339 if (!accept_ra(in6_dev))
1342 #ifdef CONFIG_IPV6_ROUTE_INFO
1343 if (ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr, NULL, 0))
1344 goto skip_routeinfo;
1346 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
1347 struct nd_opt_hdr *p;
1348 for (p = ndopts.nd_opts_ri;
1350 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
1351 struct route_info *ri = (struct route_info *)p;
1352 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1353 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT &&
1354 ri->prefix_len == 0)
1357 if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
1359 rt6_route_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3,
1360 &ipv6_hdr(skb)->saddr);
1367 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1368 /* skip link-specific ndopts from interior routers */
1369 if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT)
1373 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
1374 struct nd_opt_hdr *p;
1375 for (p = ndopts.nd_opts_pi;
1377 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1378 addrconf_prefix_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3);
1382 if (ndopts.nd_opts_mtu) {
1386 memcpy(&n, ((u8*)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1389 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1390 ND_PRINTK2(KERN_WARNING
1391 "ICMPv6 RA: invalid mtu: %d\n",
1393 } else if (in6_dev->cnf.mtu6 != mtu) {
1394 in6_dev->cnf.mtu6 = mtu;
1397 dst_metric_set(&rt->dst, RTAX_MTU, mtu);
1399 rt6_mtu_change(skb->dev, mtu);
1403 if (ndopts.nd_useropts) {
1404 struct nd_opt_hdr *p;
1405 for (p = ndopts.nd_useropts;
1407 p = ndisc_next_useropt(p, ndopts.nd_useropts_end)) {
1408 ndisc_ra_useropt(skb, p);
1412 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1413 ND_PRINTK2(KERN_WARNING
1414 "ICMPv6 RA: invalid RA options");
1418 dst_release(&rt->dst);
1420 neigh_release(neigh);
1423 static void ndisc_redirect_rcv(struct sk_buff *skb)
1425 struct inet6_dev *in6_dev;
1426 struct icmp6hdr *icmph;
1427 const struct in6_addr *dest;
1428 const struct in6_addr *target; /* new first hop to destination */
1429 struct neighbour *neigh;
1431 struct ndisc_options ndopts;
1435 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1436 switch (skb->ndisc_nodetype) {
1437 case NDISC_NODETYPE_HOST:
1438 case NDISC_NODETYPE_NODEFAULT:
1439 ND_PRINTK2(KERN_WARNING
1440 "ICMPv6 Redirect: from host or unauthorized router\n");
1445 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1446 ND_PRINTK2(KERN_WARNING
1447 "ICMPv6 Redirect: source address is not link-local.\n");
1451 optlen = skb->tail - skb->transport_header;
1452 optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1455 ND_PRINTK2(KERN_WARNING
1456 "ICMPv6 Redirect: packet too short\n");
1460 icmph = icmp6_hdr(skb);
1461 target = (const struct in6_addr *) (icmph + 1);
1464 if (ipv6_addr_is_multicast(dest)) {
1465 ND_PRINTK2(KERN_WARNING
1466 "ICMPv6 Redirect: destination address is multicast.\n");
1470 if (ipv6_addr_equal(dest, target)) {
1472 } else if (ipv6_addr_type(target) !=
1473 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1474 ND_PRINTK2(KERN_WARNING
1475 "ICMPv6 Redirect: target address is not link-local unicast.\n");
1479 in6_dev = __in6_dev_get(skb->dev);
1482 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
1486 * The IP source address of the Redirect MUST be the same as the current
1487 * first-hop router for the specified ICMP Destination Address.
1490 if (!ndisc_parse_options((u8*)(dest + 1), optlen, &ndopts)) {
1491 ND_PRINTK2(KERN_WARNING
1492 "ICMPv6 Redirect: invalid ND options\n");
1495 if (ndopts.nd_opts_tgt_lladdr) {
1496 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
1499 ND_PRINTK2(KERN_WARNING
1500 "ICMPv6 Redirect: invalid link-layer address length\n");
1505 neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1);
1507 rt6_redirect(dest, &ipv6_hdr(skb)->daddr,
1508 &ipv6_hdr(skb)->saddr, neigh, lladdr,
1510 neigh_release(neigh);
1514 void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
1515 const struct in6_addr *target)
1517 struct net_device *dev = skb->dev;
1518 struct net *net = dev_net(dev);
1519 struct sock *sk = net->ipv6.ndisc_sk;
1520 int len = sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1521 struct sk_buff *buff;
1522 struct icmp6hdr *icmph;
1523 struct in6_addr saddr_buf;
1524 struct in6_addr *addrp;
1525 struct rt6_info *rt;
1526 struct dst_entry *dst;
1527 struct inet6_dev *idev;
1533 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
1535 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
1536 ND_PRINTK2(KERN_WARNING
1537 "ICMPv6 Redirect: no link-local address on %s\n",
1542 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
1543 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1544 ND_PRINTK2(KERN_WARNING
1545 "ICMPv6 Redirect: target address is not link-local unicast.\n");
1549 icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT,
1550 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex);
1552 dst = ip6_route_output(net, NULL, &fl6);
1556 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
1560 rt = (struct rt6_info *) dst;
1562 if (rt->rt6i_flags & RTF_GATEWAY) {
1563 ND_PRINTK2(KERN_WARNING
1564 "ICMPv6 Redirect: destination is not a neighbour.\n");
1568 rt6_bind_peer(rt, 1);
1569 if (!inet_peer_xrlim_allow(rt->rt6i_peer, 1*HZ))
1572 if (dev->addr_len) {
1573 read_lock_bh(&neigh->lock);
1574 if (neigh->nud_state & NUD_VALID) {
1575 memcpy(ha_buf, neigh->ha, dev->addr_len);
1576 read_unlock_bh(&neigh->lock);
1578 len += ndisc_opt_addr_space(dev);
1580 read_unlock_bh(&neigh->lock);
1583 rd_len = min_t(unsigned int,
1584 IPV6_MIN_MTU-sizeof(struct ipv6hdr)-len, skb->len + 8);
1588 hlen = LL_RESERVED_SPACE(dev);
1589 tlen = dev->needed_tailroom;
1590 buff = sock_alloc_send_skb(sk,
1591 (MAX_HEADER + sizeof(struct ipv6hdr) +
1596 "ICMPv6 Redirect: %s() failed to allocate an skb, err=%d.\n",
1601 skb_reserve(buff, hlen);
1602 ip6_nd_hdr(sk, buff, dev, &saddr_buf, &ipv6_hdr(skb)->saddr,
1603 IPPROTO_ICMPV6, len);
1605 skb_set_transport_header(buff, skb_tail_pointer(buff) - buff->data);
1607 icmph = icmp6_hdr(buff);
1609 memset(icmph, 0, sizeof(struct icmp6hdr));
1610 icmph->icmp6_type = NDISC_REDIRECT;
1613 * copy target and destination addresses
1616 addrp = (struct in6_addr *)(icmph + 1);
1619 *addrp = ipv6_hdr(skb)->daddr;
1621 opt = (u8*) (addrp + 1);
1624 * include target_address option
1628 opt = ndisc_fill_addr_option(opt, ND_OPT_TARGET_LL_ADDR, ha,
1629 dev->addr_len, dev->type);
1632 * build redirect option and copy skb over to the new packet.
1636 *(opt++) = ND_OPT_REDIRECT_HDR;
1637 *(opt++) = (rd_len >> 3);
1640 memcpy(opt, ipv6_hdr(skb), rd_len - 8);
1642 icmph->icmp6_cksum = csum_ipv6_magic(&saddr_buf, &ipv6_hdr(skb)->saddr,
1643 len, IPPROTO_ICMPV6,
1644 csum_partial(icmph, len, 0));
1646 skb_dst_set(buff, dst);
1648 idev = __in6_dev_get(dst->dev);
1649 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
1650 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, buff, NULL, dst->dev,
1653 ICMP6MSGOUT_INC_STATS(net, idev, NDISC_REDIRECT);
1654 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1664 static void pndisc_redo(struct sk_buff *skb)
1670 int ndisc_rcv(struct sk_buff *skb)
1674 if (!pskb_may_pull(skb, skb->len))
1677 msg = (struct nd_msg *)skb_transport_header(skb);
1679 __skb_push(skb, skb->data - skb_transport_header(skb));
1681 if (ipv6_hdr(skb)->hop_limit != 255) {
1682 ND_PRINTK2(KERN_WARNING
1683 "ICMPv6 NDISC: invalid hop-limit: %d\n",
1684 ipv6_hdr(skb)->hop_limit);
1688 if (msg->icmph.icmp6_code != 0) {
1689 ND_PRINTK2(KERN_WARNING
1690 "ICMPv6 NDISC: invalid ICMPv6 code: %d\n",
1691 msg->icmph.icmp6_code);
1695 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1697 switch (msg->icmph.icmp6_type) {
1698 case NDISC_NEIGHBOUR_SOLICITATION:
1702 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1706 case NDISC_ROUTER_SOLICITATION:
1710 case NDISC_ROUTER_ADVERTISEMENT:
1711 ndisc_router_discovery(skb);
1714 case NDISC_REDIRECT:
1715 ndisc_redirect_rcv(skb);
1722 static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1724 struct net_device *dev = ptr;
1725 struct net *net = dev_net(dev);
1728 case NETDEV_CHANGEADDR:
1729 neigh_changeaddr(&nd_tbl, dev);
1730 fib6_run_gc(~0UL, net);
1733 neigh_ifdown(&nd_tbl, dev);
1734 fib6_run_gc(~0UL, net);
1736 case NETDEV_NOTIFY_PEERS:
1737 ndisc_send_unsol_na(dev);
1746 static struct notifier_block ndisc_netdev_notifier = {
1747 .notifier_call = ndisc_netdev_event,
1750 #ifdef CONFIG_SYSCTL
1751 static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
1752 const char *func, const char *dev_name)
1754 static char warncomm[TASK_COMM_LEN];
1756 if (strcmp(warncomm, current->comm) && warned < 5) {
1757 strcpy(warncomm, current->comm);
1759 "process `%s' is using deprecated sysctl (%s) "
1760 "net.ipv6.neigh.%s.%s; "
1761 "Use net.ipv6.neigh.%s.%s_ms "
1764 dev_name, ctl->procname,
1765 dev_name, ctl->procname);
1770 int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void __user *buffer, size_t *lenp, loff_t *ppos)
1772 struct net_device *dev = ctl->extra1;
1773 struct inet6_dev *idev;
1776 if ((strcmp(ctl->procname, "retrans_time") == 0) ||
1777 (strcmp(ctl->procname, "base_reachable_time") == 0))
1778 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1780 if (strcmp(ctl->procname, "retrans_time") == 0)
1781 ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
1783 else if (strcmp(ctl->procname, "base_reachable_time") == 0)
1784 ret = proc_dointvec_jiffies(ctl, write,
1785 buffer, lenp, ppos);
1787 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
1788 (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
1789 ret = proc_dointvec_ms_jiffies(ctl, write,
1790 buffer, lenp, ppos);
1794 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1795 if (ctl->data == &idev->nd_parms->base_reachable_time)
1796 idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
1797 idev->tstamp = jiffies;
1798 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1807 static int __net_init ndisc_net_init(struct net *net)
1809 struct ipv6_pinfo *np;
1813 err = inet_ctl_sock_create(&sk, PF_INET6,
1814 SOCK_RAW, IPPROTO_ICMPV6, net);
1817 "ICMPv6 NDISC: Failed to initialize the control socket (err %d).\n",
1822 net->ipv6.ndisc_sk = sk;
1825 np->hop_limit = 255;
1826 /* Do not loopback ndisc messages */
1832 static void __net_exit ndisc_net_exit(struct net *net)
1834 inet_ctl_sock_destroy(net->ipv6.ndisc_sk);
1837 static struct pernet_operations ndisc_net_ops = {
1838 .init = ndisc_net_init,
1839 .exit = ndisc_net_exit,
1842 int __init ndisc_init(void)
1846 err = register_pernet_subsys(&ndisc_net_ops);
1850 * Initialize the neighbour table
1852 neigh_table_init(&nd_tbl);
1854 #ifdef CONFIG_SYSCTL
1855 err = neigh_sysctl_register(NULL, &nd_tbl.parms, "ipv6",
1856 &ndisc_ifinfo_sysctl_change);
1858 goto out_unregister_pernet;
1860 err = register_netdevice_notifier(&ndisc_netdev_notifier);
1862 goto out_unregister_sysctl;
1866 out_unregister_sysctl:
1867 #ifdef CONFIG_SYSCTL
1868 neigh_sysctl_unregister(&nd_tbl.parms);
1869 out_unregister_pernet:
1871 unregister_pernet_subsys(&ndisc_net_ops);
1875 void ndisc_cleanup(void)
1877 unregister_netdevice_notifier(&ndisc_netdev_notifier);
1878 #ifdef CONFIG_SYSCTL
1879 neigh_sysctl_unregister(&nd_tbl.parms);
1881 neigh_table_clear(&nd_tbl);
1882 unregister_pernet_subsys(&ndisc_net_ops);