1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Neighbour Discovery for IPv6
4 * Linux INET6 implementation
7 * Pedro Roque <roque@di.fc.ul.pt>
8 * Mike Shaver <shaver@ingenia.com>
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
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
26 #define pr_fmt(fmt) "ICMPv6: " fmt
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>
41 #include <linux/sysctl.h>
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>
55 #include <net/protocol.h>
56 #include <net/ndisc.h>
57 #include <net/ip6_route.h>
58 #include <net/addrconf.h>
61 #include <net/netlink.h>
62 #include <linux/rtnetlink.h>
65 #include <net/ip6_checksum.h>
66 #include <net/inet_common.h>
67 #include <linux/proc_fs.h>
69 #include <linux/netfilter.h>
70 #include <linux/netfilter_ipv6.h>
72 static u32
ndisc_hash(const void *pkey
,
73 const struct net_device
*dev
,
75 static bool ndisc_key_eq(const struct neighbour
*neigh
, const void *pkey
);
76 static bool ndisc_allow_add(const struct net_device
*dev
,
77 struct netlink_ext_ack
*extack
);
78 static int ndisc_constructor(struct neighbour
*neigh
);
79 static void ndisc_solicit(struct neighbour
*neigh
, struct sk_buff
*skb
);
80 static void ndisc_error_report(struct neighbour
*neigh
, struct sk_buff
*skb
);
81 static int pndisc_constructor(struct pneigh_entry
*n
);
82 static void pndisc_destructor(struct pneigh_entry
*n
);
83 static void pndisc_redo(struct sk_buff
*skb
);
85 static const struct neigh_ops ndisc_generic_ops
= {
87 .solicit
= ndisc_solicit
,
88 .error_report
= ndisc_error_report
,
89 .output
= neigh_resolve_output
,
90 .connected_output
= neigh_connected_output
,
93 static const struct neigh_ops ndisc_hh_ops
= {
95 .solicit
= ndisc_solicit
,
96 .error_report
= ndisc_error_report
,
97 .output
= neigh_resolve_output
,
98 .connected_output
= neigh_resolve_output
,
102 static const struct neigh_ops ndisc_direct_ops
= {
104 .output
= neigh_direct_output
,
105 .connected_output
= neigh_direct_output
,
108 struct neigh_table nd_tbl
= {
110 .key_len
= sizeof(struct in6_addr
),
111 .protocol
= cpu_to_be16(ETH_P_IPV6
),
113 .key_eq
= ndisc_key_eq
,
114 .constructor
= ndisc_constructor
,
115 .pconstructor
= pndisc_constructor
,
116 .pdestructor
= pndisc_destructor
,
117 .proxy_redo
= pndisc_redo
,
118 .allow_add
= ndisc_allow_add
,
122 .reachable_time
= ND_REACHABLE_TIME
,
124 [NEIGH_VAR_MCAST_PROBES
] = 3,
125 [NEIGH_VAR_UCAST_PROBES
] = 3,
126 [NEIGH_VAR_RETRANS_TIME
] = ND_RETRANS_TIMER
,
127 [NEIGH_VAR_BASE_REACHABLE_TIME
] = ND_REACHABLE_TIME
,
128 [NEIGH_VAR_DELAY_PROBE_TIME
] = 5 * HZ
,
129 [NEIGH_VAR_GC_STALETIME
] = 60 * HZ
,
130 [NEIGH_VAR_QUEUE_LEN_BYTES
] = SK_WMEM_MAX
,
131 [NEIGH_VAR_PROXY_QLEN
] = 64,
132 [NEIGH_VAR_ANYCAST_DELAY
] = 1 * HZ
,
133 [NEIGH_VAR_PROXY_DELAY
] = (8 * HZ
) / 10,
136 .gc_interval
= 30 * HZ
,
141 EXPORT_SYMBOL_GPL(nd_tbl
);
143 void __ndisc_fill_addr_option(struct sk_buff
*skb
, int type
, void *data
,
144 int data_len
, int pad
)
146 int space
= __ndisc_opt_addr_space(data_len
, pad
);
147 u8
*opt
= skb_put(skb
, space
);
152 memset(opt
+ 2, 0, pad
);
156 memcpy(opt
+2, data
, data_len
);
161 memset(opt
, 0, space
);
163 EXPORT_SYMBOL_GPL(__ndisc_fill_addr_option
);
165 static inline void ndisc_fill_addr_option(struct sk_buff
*skb
, int type
,
166 void *data
, u8 icmp6_type
)
168 __ndisc_fill_addr_option(skb
, type
, data
, skb
->dev
->addr_len
,
169 ndisc_addr_option_pad(skb
->dev
->type
));
170 ndisc_ops_fill_addr_option(skb
->dev
, skb
, icmp6_type
);
173 static inline void ndisc_fill_redirect_addr_option(struct sk_buff
*skb
,
177 ndisc_fill_addr_option(skb
, ND_OPT_TARGET_LL_ADDR
, ha
, NDISC_REDIRECT
);
178 ndisc_ops_fill_redirect_addr_option(skb
->dev
, skb
, ops_data
);
181 static struct nd_opt_hdr
*ndisc_next_option(struct nd_opt_hdr
*cur
,
182 struct nd_opt_hdr
*end
)
185 if (!cur
|| !end
|| cur
>= end
)
187 type
= cur
->nd_opt_type
;
189 cur
= ((void *)cur
) + (cur
->nd_opt_len
<< 3);
190 } while (cur
< end
&& cur
->nd_opt_type
!= type
);
191 return cur
<= end
&& cur
->nd_opt_type
== type
? cur
: NULL
;
194 static inline int ndisc_is_useropt(const struct net_device
*dev
,
195 struct nd_opt_hdr
*opt
)
197 return opt
->nd_opt_type
== ND_OPT_RDNSS
||
198 opt
->nd_opt_type
== ND_OPT_DNSSL
||
199 opt
->nd_opt_type
== ND_OPT_CAPTIVE_PORTAL
||
200 ndisc_ops_is_useropt(dev
, opt
->nd_opt_type
);
203 static struct nd_opt_hdr
*ndisc_next_useropt(const struct net_device
*dev
,
204 struct nd_opt_hdr
*cur
,
205 struct nd_opt_hdr
*end
)
207 if (!cur
|| !end
|| cur
>= end
)
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
;
215 struct ndisc_options
*ndisc_parse_options(const struct net_device
*dev
,
216 u8
*opt
, int opt_len
,
217 struct ndisc_options
*ndopts
)
219 struct nd_opt_hdr
*nd_opt
= (struct nd_opt_hdr
*)opt
;
221 if (!nd_opt
|| opt_len
< 0 || !ndopts
)
223 memset(ndopts
, 0, sizeof(*ndopts
));
226 if (opt_len
< sizeof(struct nd_opt_hdr
))
228 l
= nd_opt
->nd_opt_len
<< 3;
229 if (opt_len
< l
|| l
== 0)
231 if (ndisc_ops_parse_options(dev
, nd_opt
, ndopts
))
233 switch (nd_opt
->nd_opt_type
) {
234 case ND_OPT_SOURCE_LL_ADDR
:
235 case ND_OPT_TARGET_LL_ADDR
:
238 case ND_OPT_REDIRECT_HDR
:
239 if (ndopts
->nd_opt_array
[nd_opt
->nd_opt_type
]) {
241 "%s: duplicated ND6 option found: type=%d\n",
242 __func__
, nd_opt
->nd_opt_type
);
244 ndopts
->nd_opt_array
[nd_opt
->nd_opt_type
] = nd_opt
;
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
;
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
;
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
;
266 * Unknown options must be silently ignored,
267 * to accommodate future extension to the
271 "%s: ignored unsupported option; type=%d, len=%d\n",
279 nd_opt
= ((void *)nd_opt
) + l
;
284 int ndisc_mc_map(const struct in6_addr
*addr
, char *buf
, struct net_device
*dev
, int dir
)
288 case ARPHRD_IEEE802
: /* Not sure. Check it later. --ANK */
290 ipv6_eth_mc_map(addr
, buf
);
293 ipv6_arcnet_mc_map(addr
, buf
);
295 case ARPHRD_INFINIBAND
:
296 ipv6_ib_mc_map(addr
, dev
->broadcast
, buf
);
299 return ipv6_ipgre_mc_map(addr
, dev
->broadcast
, buf
);
302 memcpy(buf
, dev
->broadcast
, dev
->addr_len
);
308 EXPORT_SYMBOL(ndisc_mc_map
);
310 static u32
ndisc_hash(const void *pkey
,
311 const struct net_device
*dev
,
314 return ndisc_hashfn(pkey
, dev
, hash_rnd
);
317 static bool ndisc_key_eq(const struct neighbour
*n
, const void *pkey
)
319 return neigh_key_eq128(n
, pkey
);
322 static int ndisc_constructor(struct neighbour
*neigh
)
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
);
330 in6_dev
= in6_dev_get(dev
);
335 parms
= in6_dev
->nd_parms
;
336 __neigh_parms_put(neigh
->parms
);
337 neigh
->parms
= neigh_parms_clone(parms
);
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
;
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
);
357 if (dev
->header_ops
->cache
)
358 neigh
->ops
= &ndisc_hh_ops
;
360 neigh
->ops
= &ndisc_generic_ops
;
361 if (neigh
->nud_state
&NUD_VALID
)
362 neigh
->output
= neigh
->ops
->connected_output
;
364 neigh
->output
= neigh
->ops
->output
;
366 in6_dev_put(in6_dev
);
370 static int pndisc_constructor(struct pneigh_entry
*n
)
372 struct in6_addr
*addr
= (struct in6_addr
*)&n
->key
;
373 struct in6_addr maddr
;
374 struct net_device
*dev
= n
->dev
;
376 if (!dev
|| !__in6_dev_get(dev
))
378 addrconf_addr_solict_mult(addr
, &maddr
);
379 ipv6_dev_mc_inc(dev
, &maddr
);
383 static void pndisc_destructor(struct pneigh_entry
*n
)
385 struct in6_addr
*addr
= (struct in6_addr
*)&n
->key
;
386 struct in6_addr maddr
;
387 struct net_device
*dev
= n
->dev
;
389 if (!dev
|| !__in6_dev_get(dev
))
391 addrconf_addr_solict_mult(addr
, &maddr
);
392 ipv6_dev_mc_dec(dev
, &maddr
);
395 /* called with rtnl held */
396 static bool ndisc_allow_add(const struct net_device
*dev
,
397 struct netlink_ext_ack
*extack
)
399 struct inet6_dev
*idev
= __in6_dev_get(dev
);
401 if (!idev
|| idev
->cnf
.disable_ipv6
) {
402 NL_SET_ERR_MSG(extack
, "IPv6 is disabled on this device");
409 static struct sk_buff
*ndisc_alloc_skb(struct net_device
*dev
,
412 int hlen
= LL_RESERVED_SPACE(dev
);
413 int tlen
= dev
->needed_tailroom
;
414 struct sock
*sk
= dev_net(dev
)->ipv6
.ndisc_sk
;
417 skb
= alloc_skb(hlen
+ sizeof(struct ipv6hdr
) + len
+ tlen
, GFP_ATOMIC
);
419 ND_PRINTK(0, err
, "ndisc: %s failed to allocate an skb\n",
424 skb
->protocol
= htons(ETH_P_IPV6
);
427 skb_reserve(skb
, hlen
+ sizeof(struct ipv6hdr
));
428 skb_reset_transport_header(skb
);
430 /* Manually assign socket ownership as we avoid calling
431 * sock_alloc_send_pskb() to bypass wmem buffer limits
433 skb_set_owner_w(skb
, sk
);
438 static void ip6_nd_hdr(struct sk_buff
*skb
,
439 const struct in6_addr
*saddr
,
440 const struct in6_addr
*daddr
,
441 int hop_limit
, int len
)
444 struct inet6_dev
*idev
;
448 idev
= __in6_dev_get(skb
->dev
);
449 tclass
= idev
? idev
->cnf
.ndisc_tclass
: 0;
452 skb_push(skb
, sizeof(*hdr
));
453 skb_reset_network_header(skb
);
456 ip6_flow_hdr(hdr
, tclass
, 0);
458 hdr
->payload_len
= htons(len
);
459 hdr
->nexthdr
= IPPROTO_ICMPV6
;
460 hdr
->hop_limit
= hop_limit
;
466 static void ndisc_send_skb(struct sk_buff
*skb
,
467 const struct in6_addr
*daddr
,
468 const struct in6_addr
*saddr
)
470 struct dst_entry
*dst
= skb_dst(skb
);
471 struct net
*net
= dev_net(skb
->dev
);
472 struct sock
*sk
= net
->ipv6
.ndisc_sk
;
473 struct inet6_dev
*idev
;
475 struct icmp6hdr
*icmp6h
= icmp6_hdr(skb
);
478 type
= icmp6h
->icmp6_type
;
482 int oif
= skb
->dev
->ifindex
;
484 icmpv6_flow_init(sk
, &fl6
, type
, saddr
, daddr
, oif
);
485 dst
= icmp6_dst_alloc(skb
->dev
, &fl6
);
491 skb_dst_set(skb
, dst
);
494 icmp6h
->icmp6_cksum
= csum_ipv6_magic(saddr
, daddr
, skb
->len
,
499 ip6_nd_hdr(skb
, saddr
, daddr
, inet6_sk(sk
)->hop_limit
, skb
->len
);
502 idev
= __in6_dev_get(dst
->dev
);
503 IP6_UPD_PO_STATS(net
, idev
, IPSTATS_MIB_OUT
, skb
->len
);
505 err
= NF_HOOK(NFPROTO_IPV6
, NF_INET_LOCAL_OUT
,
506 net
, sk
, skb
, NULL
, dst
->dev
,
509 ICMP6MSGOUT_INC_STATS(net
, idev
, type
);
510 ICMP6_INC_STATS(net
, idev
, ICMP6_MIB_OUTMSGS
);
516 void ndisc_send_na(struct net_device
*dev
, const struct in6_addr
*daddr
,
517 const struct in6_addr
*solicited_addr
,
518 bool router
, bool solicited
, bool override
, bool inc_opt
)
521 struct in6_addr tmpaddr
;
522 struct inet6_ifaddr
*ifp
;
523 const struct in6_addr
*src_addr
;
527 /* for anycast or proxy, solicited_addr != src_addr */
528 ifp
= ipv6_get_ifaddr(dev_net(dev
), solicited_addr
, dev
, 1);
530 src_addr
= solicited_addr
;
531 if (ifp
->flags
& IFA_F_OPTIMISTIC
)
533 inc_opt
|= ifp
->idev
->cnf
.force_tllao
;
536 if (ipv6_dev_get_saddr(dev_net(dev
), dev
, daddr
,
537 inet6_sk(dev_net(dev
)->ipv6
.ndisc_sk
)->srcprefs
,
546 optlen
+= ndisc_opt_addr_space(dev
,
547 NDISC_NEIGHBOUR_ADVERTISEMENT
);
549 skb
= ndisc_alloc_skb(dev
, sizeof(*msg
) + optlen
);
553 msg
= skb_put(skb
, sizeof(*msg
));
554 *msg
= (struct nd_msg
) {
556 .icmp6_type
= NDISC_NEIGHBOUR_ADVERTISEMENT
,
557 .icmp6_router
= router
,
558 .icmp6_solicited
= solicited
,
559 .icmp6_override
= override
,
561 .target
= *solicited_addr
,
565 ndisc_fill_addr_option(skb
, ND_OPT_TARGET_LL_ADDR
,
567 NDISC_NEIGHBOUR_ADVERTISEMENT
);
569 ndisc_send_skb(skb
, daddr
, src_addr
);
572 static void ndisc_send_unsol_na(struct net_device
*dev
)
574 struct inet6_dev
*idev
;
575 struct inet6_ifaddr
*ifa
;
577 idev
= in6_dev_get(dev
);
581 read_lock_bh(&idev
->lock
);
582 list_for_each_entry(ifa
, &idev
->addr_list
, if_list
) {
583 /* skip tentative addresses until dad completes */
584 if (ifa
->flags
& IFA_F_TENTATIVE
&&
585 !(ifa
->flags
& IFA_F_OPTIMISTIC
))
588 ndisc_send_na(dev
, &in6addr_linklocal_allnodes
, &ifa
->addr
,
589 /*router=*/ !!idev
->cnf
.forwarding
,
590 /*solicited=*/ false, /*override=*/ true,
593 read_unlock_bh(&idev
->lock
);
598 void ndisc_send_ns(struct net_device
*dev
, const struct in6_addr
*solicit
,
599 const struct in6_addr
*daddr
, const struct in6_addr
*saddr
,
603 struct in6_addr addr_buf
;
604 int inc_opt
= dev
->addr_len
;
609 if (ipv6_get_lladdr(dev
, &addr_buf
,
610 (IFA_F_TENTATIVE
|IFA_F_OPTIMISTIC
)))
615 if (ipv6_addr_any(saddr
))
618 optlen
+= ndisc_opt_addr_space(dev
,
619 NDISC_NEIGHBOUR_SOLICITATION
);
623 skb
= ndisc_alloc_skb(dev
, sizeof(*msg
) + optlen
);
627 msg
= skb_put(skb
, sizeof(*msg
));
628 *msg
= (struct nd_msg
) {
630 .icmp6_type
= NDISC_NEIGHBOUR_SOLICITATION
,
636 ndisc_fill_addr_option(skb
, ND_OPT_SOURCE_LL_ADDR
,
638 NDISC_NEIGHBOUR_SOLICITATION
);
640 u8
*opt
= skb_put(skb
, 8);
642 opt
[0] = ND_OPT_NONCE
;
644 memcpy(opt
+ 2, &nonce
, 6);
647 ndisc_send_skb(skb
, daddr
, saddr
);
650 void ndisc_send_rs(struct net_device
*dev
, const struct in6_addr
*saddr
,
651 const struct in6_addr
*daddr
)
655 int send_sllao
= dev
->addr_len
;
658 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
660 * According to section 2.2 of RFC 4429, we must not
661 * send router solicitations with a sllao from
662 * optimistic addresses, but we may send the solicitation
663 * if we don't include the sllao. So here we check
664 * if our address is optimistic, and if so, we
665 * suppress the inclusion of the sllao.
668 struct inet6_ifaddr
*ifp
= ipv6_get_ifaddr(dev_net(dev
), saddr
,
671 if (ifp
->flags
& IFA_F_OPTIMISTIC
) {
681 optlen
+= ndisc_opt_addr_space(dev
, NDISC_ROUTER_SOLICITATION
);
683 skb
= ndisc_alloc_skb(dev
, sizeof(*msg
) + optlen
);
687 msg
= skb_put(skb
, sizeof(*msg
));
688 *msg
= (struct rs_msg
) {
690 .icmp6_type
= NDISC_ROUTER_SOLICITATION
,
695 ndisc_fill_addr_option(skb
, ND_OPT_SOURCE_LL_ADDR
,
697 NDISC_ROUTER_SOLICITATION
);
699 ndisc_send_skb(skb
, daddr
, saddr
);
703 static void ndisc_error_report(struct neighbour
*neigh
, struct sk_buff
*skb
)
706 * "The sender MUST return an ICMP
707 * destination unreachable"
709 dst_link_failure(skb
);
713 /* Called with locked neigh: either read or both */
715 static void ndisc_solicit(struct neighbour
*neigh
, struct sk_buff
*skb
)
717 struct in6_addr
*saddr
= NULL
;
718 struct in6_addr mcaddr
;
719 struct net_device
*dev
= neigh
->dev
;
720 struct in6_addr
*target
= (struct in6_addr
*)&neigh
->primary_key
;
721 int probes
= atomic_read(&neigh
->probes
);
723 if (skb
&& ipv6_chk_addr_and_flags(dev_net(dev
), &ipv6_hdr(skb
)->saddr
,
725 IFA_F_TENTATIVE
|IFA_F_OPTIMISTIC
))
726 saddr
= &ipv6_hdr(skb
)->saddr
;
727 probes
-= NEIGH_VAR(neigh
->parms
, UCAST_PROBES
);
729 if (!(neigh
->nud_state
& NUD_VALID
)) {
731 "%s: trying to ucast probe in NUD_INVALID: %pI6\n",
734 ndisc_send_ns(dev
, target
, target
, saddr
, 0);
735 } else if ((probes
-= NEIGH_VAR(neigh
->parms
, APP_PROBES
)) < 0) {
738 addrconf_addr_solict_mult(target
, &mcaddr
);
739 ndisc_send_ns(dev
, target
, &mcaddr
, saddr
, 0);
743 static int pndisc_is_router(const void *pkey
,
744 struct net_device
*dev
)
746 struct pneigh_entry
*n
;
749 read_lock_bh(&nd_tbl
.lock
);
750 n
= __pneigh_lookup(&nd_tbl
, dev_net(dev
), pkey
, dev
);
752 ret
= !!(n
->flags
& NTF_ROUTER
);
753 read_unlock_bh(&nd_tbl
.lock
);
758 void ndisc_update(const struct net_device
*dev
, struct neighbour
*neigh
,
759 const u8
*lladdr
, u8
new, u32 flags
, u8 icmp6_type
,
760 struct ndisc_options
*ndopts
)
762 neigh_update(neigh
, lladdr
, new, flags
, 0);
763 /* report ndisc ops about neighbour update */
764 ndisc_ops_update(dev
, neigh
, flags
, icmp6_type
, ndopts
);
767 static void ndisc_recv_ns(struct sk_buff
*skb
)
769 struct nd_msg
*msg
= (struct nd_msg
*)skb_transport_header(skb
);
770 const struct in6_addr
*saddr
= &ipv6_hdr(skb
)->saddr
;
771 const struct in6_addr
*daddr
= &ipv6_hdr(skb
)->daddr
;
773 u32 ndoptlen
= skb_tail_pointer(skb
) - (skb_transport_header(skb
) +
774 offsetof(struct nd_msg
, opt
));
775 struct ndisc_options ndopts
;
776 struct net_device
*dev
= skb
->dev
;
777 struct inet6_ifaddr
*ifp
;
778 struct inet6_dev
*idev
= NULL
;
779 struct neighbour
*neigh
;
780 int dad
= ipv6_addr_any(saddr
);
785 if (skb
->len
< sizeof(struct nd_msg
)) {
786 ND_PRINTK(2, warn
, "NS: packet too short\n");
790 if (ipv6_addr_is_multicast(&msg
->target
)) {
791 ND_PRINTK(2, warn
, "NS: multicast target address\n");
797 * DAD has to be destined for solicited node multicast address.
799 if (dad
&& !ipv6_addr_is_solict_mult(daddr
)) {
800 ND_PRINTK(2, warn
, "NS: bad DAD packet (wrong destination)\n");
804 if (!ndisc_parse_options(dev
, msg
->opt
, ndoptlen
, &ndopts
)) {
805 ND_PRINTK(2, warn
, "NS: invalid ND options\n");
809 if (ndopts
.nd_opts_src_lladdr
) {
810 lladdr
= ndisc_opt_addr_data(ndopts
.nd_opts_src_lladdr
, dev
);
813 "NS: invalid link-layer address length\n");
818 * If the IP source address is the unspecified address,
819 * there MUST NOT be source link-layer address option
824 "NS: bad DAD packet (link-layer address option)\n");
828 if (ndopts
.nd_opts_nonce
&& ndopts
.nd_opts_nonce
->nd_opt_len
== 1)
829 memcpy(&nonce
, (u8
*)(ndopts
.nd_opts_nonce
+ 1), 6);
831 inc
= ipv6_addr_is_multicast(daddr
);
833 ifp
= ipv6_get_ifaddr(dev_net(dev
), &msg
->target
, dev
, 1);
836 if (ifp
->flags
& (IFA_F_TENTATIVE
|IFA_F_OPTIMISTIC
)) {
838 if (nonce
!= 0 && ifp
->dad_nonce
== nonce
) {
839 u8
*np
= (u8
*)&nonce
;
840 /* Matching nonce if looped back */
842 "%s: IPv6 DAD loopback for address %pI6c nonce %pM ignored\n",
843 ifp
->idev
->dev
->name
,
848 * We are colliding with another node
850 * so fail our DAD process
852 addrconf_dad_failure(skb
, ifp
);
856 * This is not a dad solicitation.
857 * If we are an optimistic node,
859 * Otherwise, we should ignore it.
861 if (!(ifp
->flags
& IFA_F_OPTIMISTIC
))
868 struct net
*net
= dev_net(dev
);
870 /* perhaps an address on the master device */
871 if (netif_is_l3_slave(dev
)) {
872 struct net_device
*mdev
;
874 mdev
= netdev_master_upper_dev_get_rcu(dev
);
876 ifp
= ipv6_get_ifaddr(net
, &msg
->target
, mdev
, 1);
882 idev
= in6_dev_get(dev
);
884 /* XXX: count this drop? */
888 if (ipv6_chk_acast_addr(net
, dev
, &msg
->target
) ||
889 (idev
->cnf
.forwarding
&&
890 (net
->ipv6
.devconf_all
->proxy_ndp
|| idev
->cnf
.proxy_ndp
) &&
891 (is_router
= pndisc_is_router(&msg
->target
, dev
)) >= 0)) {
892 if (!(NEIGH_CB(skb
)->flags
& LOCALLY_ENQUEUED
) &&
893 skb
->pkt_type
!= PACKET_HOST
&&
895 NEIGH_VAR(idev
->nd_parms
, PROXY_DELAY
) != 0) {
897 * for anycast or proxy,
898 * sender should delay its response
899 * by a random time between 0 and
900 * MAX_ANYCAST_DELAY_TIME seconds.
901 * (RFC2461) -- yoshfuji
903 struct sk_buff
*n
= skb_clone(skb
, GFP_ATOMIC
);
905 pneigh_enqueue(&nd_tbl
, idev
->nd_parms
, n
);
913 is_router
= idev
->cnf
.forwarding
;
916 ndisc_send_na(dev
, &in6addr_linklocal_allnodes
, &msg
->target
,
917 !!is_router
, false, (ifp
!= NULL
), true);
922 NEIGH_CACHE_STAT_INC(&nd_tbl
, rcv_probes_mcast
);
924 NEIGH_CACHE_STAT_INC(&nd_tbl
, rcv_probes_ucast
);
927 * update / create cache entry
928 * for the source address
930 neigh
= __neigh_lookup(&nd_tbl
, saddr
, dev
,
931 !inc
|| lladdr
|| !dev
->addr_len
);
933 ndisc_update(dev
, neigh
, lladdr
, NUD_STALE
,
934 NEIGH_UPDATE_F_WEAK_OVERRIDE
|
935 NEIGH_UPDATE_F_OVERRIDE
,
936 NDISC_NEIGHBOUR_SOLICITATION
, &ndopts
);
937 if (neigh
|| !dev
->header_ops
) {
938 ndisc_send_na(dev
, saddr
, &msg
->target
, !!is_router
,
939 true, (ifp
!= NULL
&& inc
), inc
);
941 neigh_release(neigh
);
951 static void ndisc_recv_na(struct sk_buff
*skb
)
953 struct nd_msg
*msg
= (struct nd_msg
*)skb_transport_header(skb
);
954 struct in6_addr
*saddr
= &ipv6_hdr(skb
)->saddr
;
955 const struct in6_addr
*daddr
= &ipv6_hdr(skb
)->daddr
;
957 u32 ndoptlen
= skb_tail_pointer(skb
) - (skb_transport_header(skb
) +
958 offsetof(struct nd_msg
, opt
));
959 struct ndisc_options ndopts
;
960 struct net_device
*dev
= skb
->dev
;
961 struct inet6_dev
*idev
= __in6_dev_get(dev
);
962 struct inet6_ifaddr
*ifp
;
963 struct neighbour
*neigh
;
965 if (skb
->len
< sizeof(struct nd_msg
)) {
966 ND_PRINTK(2, warn
, "NA: packet too short\n");
970 if (ipv6_addr_is_multicast(&msg
->target
)) {
971 ND_PRINTK(2, warn
, "NA: target address is multicast\n");
975 if (ipv6_addr_is_multicast(daddr
) &&
976 msg
->icmph
.icmp6_solicited
) {
977 ND_PRINTK(2, warn
, "NA: solicited NA is multicasted\n");
981 /* For some 802.11 wireless deployments (and possibly other networks),
982 * there will be a NA proxy and unsolicitd packets are attacks
983 * and thus should not be accepted.
985 if (!msg
->icmph
.icmp6_solicited
&& idev
&&
986 idev
->cnf
.drop_unsolicited_na
)
989 if (!ndisc_parse_options(dev
, msg
->opt
, ndoptlen
, &ndopts
)) {
990 ND_PRINTK(2, warn
, "NS: invalid ND option\n");
993 if (ndopts
.nd_opts_tgt_lladdr
) {
994 lladdr
= ndisc_opt_addr_data(ndopts
.nd_opts_tgt_lladdr
, dev
);
997 "NA: invalid link-layer address length\n");
1001 ifp
= ipv6_get_ifaddr(dev_net(dev
), &msg
->target
, dev
, 1);
1003 if (skb
->pkt_type
!= PACKET_LOOPBACK
1004 && (ifp
->flags
& IFA_F_TENTATIVE
)) {
1005 addrconf_dad_failure(skb
, ifp
);
1008 /* What should we make now? The advertisement
1009 is invalid, but ndisc specs say nothing
1010 about it. It could be misconfiguration, or
1011 an smart proxy agent tries to help us :-)
1013 We should not print the error if NA has been
1014 received from loopback - it is just our own
1015 unsolicited advertisement.
1017 if (skb
->pkt_type
!= PACKET_LOOPBACK
)
1019 "NA: %pM advertised our address %pI6c on %s!\n",
1020 eth_hdr(skb
)->h_source
, &ifp
->addr
, ifp
->idev
->dev
->name
);
1024 neigh
= neigh_lookup(&nd_tbl
, &msg
->target
, dev
);
1027 u8 old_flags
= neigh
->flags
;
1028 struct net
*net
= dev_net(dev
);
1030 if (neigh
->nud_state
& NUD_FAILED
)
1034 * Don't update the neighbor cache entry on a proxy NA from
1035 * ourselves because either the proxied node is off link or it
1036 * has already sent a NA to us.
1038 if (lladdr
&& !memcmp(lladdr
, dev
->dev_addr
, dev
->addr_len
) &&
1039 net
->ipv6
.devconf_all
->forwarding
&& net
->ipv6
.devconf_all
->proxy_ndp
&&
1040 pneigh_lookup(&nd_tbl
, net
, &msg
->target
, dev
, 0)) {
1041 /* XXX: idev->cnf.proxy_ndp */
1045 ndisc_update(dev
, neigh
, lladdr
,
1046 msg
->icmph
.icmp6_solicited
? NUD_REACHABLE
: NUD_STALE
,
1047 NEIGH_UPDATE_F_WEAK_OVERRIDE
|
1048 (msg
->icmph
.icmp6_override
? NEIGH_UPDATE_F_OVERRIDE
: 0)|
1049 NEIGH_UPDATE_F_OVERRIDE_ISROUTER
|
1050 (msg
->icmph
.icmp6_router
? NEIGH_UPDATE_F_ISROUTER
: 0),
1051 NDISC_NEIGHBOUR_ADVERTISEMENT
, &ndopts
);
1053 if ((old_flags
& ~neigh
->flags
) & NTF_ROUTER
) {
1055 * Change: router to host
1057 rt6_clean_tohost(dev_net(dev
), saddr
);
1061 neigh_release(neigh
);
1065 static void ndisc_recv_rs(struct sk_buff
*skb
)
1067 struct rs_msg
*rs_msg
= (struct rs_msg
*)skb_transport_header(skb
);
1068 unsigned long ndoptlen
= skb
->len
- sizeof(*rs_msg
);
1069 struct neighbour
*neigh
;
1070 struct inet6_dev
*idev
;
1071 const struct in6_addr
*saddr
= &ipv6_hdr(skb
)->saddr
;
1072 struct ndisc_options ndopts
;
1075 if (skb
->len
< sizeof(*rs_msg
))
1078 idev
= __in6_dev_get(skb
->dev
);
1080 ND_PRINTK(1, err
, "RS: can't find in6 device\n");
1084 /* Don't accept RS if we're not in router mode */
1085 if (!idev
->cnf
.forwarding
)
1089 * Don't update NCE if src = ::;
1090 * this implies that the source node has no ip address assigned yet.
1092 if (ipv6_addr_any(saddr
))
1095 /* Parse ND options */
1096 if (!ndisc_parse_options(skb
->dev
, rs_msg
->opt
, ndoptlen
, &ndopts
)) {
1097 ND_PRINTK(2, notice
, "NS: invalid ND option, ignored\n");
1101 if (ndopts
.nd_opts_src_lladdr
) {
1102 lladdr
= ndisc_opt_addr_data(ndopts
.nd_opts_src_lladdr
,
1108 neigh
= __neigh_lookup(&nd_tbl
, saddr
, skb
->dev
, 1);
1110 ndisc_update(skb
->dev
, neigh
, lladdr
, NUD_STALE
,
1111 NEIGH_UPDATE_F_WEAK_OVERRIDE
|
1112 NEIGH_UPDATE_F_OVERRIDE
|
1113 NEIGH_UPDATE_F_OVERRIDE_ISROUTER
,
1114 NDISC_ROUTER_SOLICITATION
, &ndopts
);
1115 neigh_release(neigh
);
1121 static void ndisc_ra_useropt(struct sk_buff
*ra
, struct nd_opt_hdr
*opt
)
1123 struct icmp6hdr
*icmp6h
= (struct icmp6hdr
*)skb_transport_header(ra
);
1124 struct sk_buff
*skb
;
1125 struct nlmsghdr
*nlh
;
1126 struct nduseroptmsg
*ndmsg
;
1127 struct net
*net
= dev_net(ra
->dev
);
1129 int base_size
= NLMSG_ALIGN(sizeof(struct nduseroptmsg
)
1130 + (opt
->nd_opt_len
<< 3));
1131 size_t msg_size
= base_size
+ nla_total_size(sizeof(struct in6_addr
));
1133 skb
= nlmsg_new(msg_size
, GFP_ATOMIC
);
1139 nlh
= nlmsg_put(skb
, 0, 0, RTM_NEWNDUSEROPT
, base_size
, 0);
1141 goto nla_put_failure
;
1144 ndmsg
= nlmsg_data(nlh
);
1145 ndmsg
->nduseropt_family
= AF_INET6
;
1146 ndmsg
->nduseropt_ifindex
= ra
->dev
->ifindex
;
1147 ndmsg
->nduseropt_icmp_type
= icmp6h
->icmp6_type
;
1148 ndmsg
->nduseropt_icmp_code
= icmp6h
->icmp6_code
;
1149 ndmsg
->nduseropt_opts_len
= opt
->nd_opt_len
<< 3;
1151 memcpy(ndmsg
+ 1, opt
, opt
->nd_opt_len
<< 3);
1153 if (nla_put_in6_addr(skb
, NDUSEROPT_SRCADDR
, &ipv6_hdr(ra
)->saddr
))
1154 goto nla_put_failure
;
1155 nlmsg_end(skb
, nlh
);
1157 rtnl_notify(skb
, net
, 0, RTNLGRP_ND_USEROPT
, NULL
, GFP_ATOMIC
);
1164 rtnl_set_sk_err(net
, RTNLGRP_ND_USEROPT
, err
);
1167 static void ndisc_router_discovery(struct sk_buff
*skb
)
1169 struct ra_msg
*ra_msg
= (struct ra_msg
*)skb_transport_header(skb
);
1170 struct neighbour
*neigh
= NULL
;
1171 struct inet6_dev
*in6_dev
;
1172 struct fib6_info
*rt
= NULL
;
1175 struct ndisc_options ndopts
;
1177 unsigned int pref
= 0;
1179 bool send_ifinfo_notify
= false;
1181 __u8
*opt
= (__u8
*)(ra_msg
+ 1);
1183 optlen
= (skb_tail_pointer(skb
) - skb_transport_header(skb
)) -
1184 sizeof(struct ra_msg
);
1187 "RA: %s, dev: %s\n",
1188 __func__
, skb
->dev
->name
);
1189 if (!(ipv6_addr_type(&ipv6_hdr(skb
)->saddr
) & IPV6_ADDR_LINKLOCAL
)) {
1190 ND_PRINTK(2, warn
, "RA: source address is not link-local\n");
1194 ND_PRINTK(2, warn
, "RA: packet too short\n");
1198 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1199 if (skb
->ndisc_nodetype
== NDISC_NODETYPE_HOST
) {
1200 ND_PRINTK(2, warn
, "RA: from host or unauthorized router\n");
1206 * set the RA_RECV flag in the interface
1209 in6_dev
= __in6_dev_get(skb
->dev
);
1211 ND_PRINTK(0, err
, "RA: can't find inet6 device for %s\n",
1216 if (!ndisc_parse_options(skb
->dev
, opt
, optlen
, &ndopts
)) {
1217 ND_PRINTK(2, warn
, "RA: invalid ND options\n");
1221 if (!ipv6_accept_ra(in6_dev
)) {
1223 "RA: %s, did not accept ra for dev: %s\n",
1224 __func__
, skb
->dev
->name
);
1225 goto skip_linkparms
;
1228 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1229 /* skip link-specific parameters from interior routers */
1230 if (skb
->ndisc_nodetype
== NDISC_NODETYPE_NODEFAULT
) {
1232 "RA: %s, nodetype is NODEFAULT, dev: %s\n",
1233 __func__
, skb
->dev
->name
);
1234 goto skip_linkparms
;
1238 if (in6_dev
->if_flags
& IF_RS_SENT
) {
1240 * flag that an RA was received after an RS was sent
1241 * out on this interface.
1243 in6_dev
->if_flags
|= IF_RA_RCVD
;
1247 * Remember the managed/otherconf flags from most recently
1248 * received RA message (RFC 2462) -- yoshfuji
1250 old_if_flags
= in6_dev
->if_flags
;
1251 in6_dev
->if_flags
= (in6_dev
->if_flags
& ~(IF_RA_MANAGED
|
1253 (ra_msg
->icmph
.icmp6_addrconf_managed
?
1254 IF_RA_MANAGED
: 0) |
1255 (ra_msg
->icmph
.icmp6_addrconf_other
?
1256 IF_RA_OTHERCONF
: 0);
1258 if (old_if_flags
!= in6_dev
->if_flags
)
1259 send_ifinfo_notify
= true;
1261 if (!in6_dev
->cnf
.accept_ra_defrtr
) {
1263 "RA: %s, defrtr is false for dev: %s\n",
1264 __func__
, skb
->dev
->name
);
1268 /* Do not accept RA with source-addr found on local machine unless
1269 * accept_ra_from_local is set to true.
1271 net
= dev_net(in6_dev
->dev
);
1272 if (!in6_dev
->cnf
.accept_ra_from_local
&&
1273 ipv6_chk_addr(net
, &ipv6_hdr(skb
)->saddr
, in6_dev
->dev
, 0)) {
1275 "RA from local address detected on dev: %s: default router ignored\n",
1280 lifetime
= ntohs(ra_msg
->icmph
.icmp6_rt_lifetime
);
1282 #ifdef CONFIG_IPV6_ROUTER_PREF
1283 pref
= ra_msg
->icmph
.icmp6_router_pref
;
1284 /* 10b is handled as if it were 00b (medium) */
1285 if (pref
== ICMPV6_ROUTER_PREF_INVALID
||
1286 !in6_dev
->cnf
.accept_ra_rtr_pref
)
1287 pref
= ICMPV6_ROUTER_PREF_MEDIUM
;
1289 /* routes added from RAs do not use nexthop objects */
1290 rt
= rt6_get_dflt_router(net
, &ipv6_hdr(skb
)->saddr
, skb
->dev
);
1292 neigh
= ip6_neigh_lookup(&rt
->fib6_nh
->fib_nh_gw6
,
1293 rt
->fib6_nh
->fib_nh_dev
, NULL
,
1294 &ipv6_hdr(skb
)->saddr
);
1297 "RA: %s got default router without neighbour\n",
1299 fib6_info_release(rt
);
1303 if (rt
&& lifetime
== 0) {
1304 ip6_del_rt(net
, rt
);
1308 ND_PRINTK(3, info
, "RA: rt: %p lifetime: %d, for dev: %s\n",
1309 rt
, lifetime
, skb
->dev
->name
);
1310 if (!rt
&& lifetime
) {
1311 ND_PRINTK(3, info
, "RA: adding default router\n");
1313 rt
= rt6_add_dflt_router(net
, &ipv6_hdr(skb
)->saddr
,
1317 "RA: %s failed to add default route\n",
1322 neigh
= ip6_neigh_lookup(&rt
->fib6_nh
->fib_nh_gw6
,
1323 rt
->fib6_nh
->fib_nh_dev
, NULL
,
1324 &ipv6_hdr(skb
)->saddr
);
1327 "RA: %s got default router without neighbour\n",
1329 fib6_info_release(rt
);
1332 neigh
->flags
|= NTF_ROUTER
;
1334 rt
->fib6_flags
= (rt
->fib6_flags
& ~RTF_PREF_MASK
) | RTF_PREF(pref
);
1338 fib6_set_expires(rt
, jiffies
+ (HZ
* lifetime
));
1339 if (in6_dev
->cnf
.accept_ra_min_hop_limit
< 256 &&
1340 ra_msg
->icmph
.icmp6_hop_limit
) {
1341 if (in6_dev
->cnf
.accept_ra_min_hop_limit
<= ra_msg
->icmph
.icmp6_hop_limit
) {
1342 in6_dev
->cnf
.hop_limit
= ra_msg
->icmph
.icmp6_hop_limit
;
1343 fib6_metric_set(rt
, RTAX_HOPLIMIT
,
1344 ra_msg
->icmph
.icmp6_hop_limit
);
1346 ND_PRINTK(2, warn
, "RA: Got route advertisement with lower hop_limit than minimum\n");
1353 * Update Reachable Time and Retrans Timer
1356 if (in6_dev
->nd_parms
) {
1357 unsigned long rtime
= ntohl(ra_msg
->retrans_timer
);
1359 if (rtime
&& rtime
/1000 < MAX_SCHEDULE_TIMEOUT
/HZ
) {
1360 rtime
= (rtime
*HZ
)/1000;
1363 NEIGH_VAR_SET(in6_dev
->nd_parms
, RETRANS_TIME
, rtime
);
1364 in6_dev
->tstamp
= jiffies
;
1365 send_ifinfo_notify
= true;
1368 rtime
= ntohl(ra_msg
->reachable_time
);
1369 if (rtime
&& rtime
/1000 < MAX_SCHEDULE_TIMEOUT
/(3*HZ
)) {
1370 rtime
= (rtime
*HZ
)/1000;
1375 if (rtime
!= NEIGH_VAR(in6_dev
->nd_parms
, BASE_REACHABLE_TIME
)) {
1376 NEIGH_VAR_SET(in6_dev
->nd_parms
,
1377 BASE_REACHABLE_TIME
, rtime
);
1378 NEIGH_VAR_SET(in6_dev
->nd_parms
,
1379 GC_STALETIME
, 3 * rtime
);
1380 in6_dev
->nd_parms
->reachable_time
= neigh_rand_reach_time(rtime
);
1381 in6_dev
->tstamp
= jiffies
;
1382 send_ifinfo_notify
= true;
1388 * Send a notify if RA changed managed/otherconf flags or timer settings
1390 if (send_ifinfo_notify
)
1391 inet6_ifinfo_notify(RTM_NEWLINK
, in6_dev
);
1400 neigh
= __neigh_lookup(&nd_tbl
, &ipv6_hdr(skb
)->saddr
,
1404 if (ndopts
.nd_opts_src_lladdr
) {
1405 lladdr
= ndisc_opt_addr_data(ndopts
.nd_opts_src_lladdr
,
1409 "RA: invalid link-layer address length\n");
1413 ndisc_update(skb
->dev
, neigh
, lladdr
, NUD_STALE
,
1414 NEIGH_UPDATE_F_WEAK_OVERRIDE
|
1415 NEIGH_UPDATE_F_OVERRIDE
|
1416 NEIGH_UPDATE_F_OVERRIDE_ISROUTER
|
1417 NEIGH_UPDATE_F_ISROUTER
,
1418 NDISC_ROUTER_ADVERTISEMENT
, &ndopts
);
1421 if (!ipv6_accept_ra(in6_dev
)) {
1423 "RA: %s, accept_ra is false for dev: %s\n",
1424 __func__
, skb
->dev
->name
);
1428 #ifdef CONFIG_IPV6_ROUTE_INFO
1429 if (!in6_dev
->cnf
.accept_ra_from_local
&&
1430 ipv6_chk_addr(dev_net(in6_dev
->dev
), &ipv6_hdr(skb
)->saddr
,
1433 "RA from local address detected on dev: %s: router info ignored.\n",
1435 goto skip_routeinfo
;
1438 if (in6_dev
->cnf
.accept_ra_rtr_pref
&& ndopts
.nd_opts_ri
) {
1439 struct nd_opt_hdr
*p
;
1440 for (p
= ndopts
.nd_opts_ri
;
1442 p
= ndisc_next_option(p
, ndopts
.nd_opts_ri_end
)) {
1443 struct route_info
*ri
= (struct route_info
*)p
;
1444 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1445 if (skb
->ndisc_nodetype
== NDISC_NODETYPE_NODEFAULT
&&
1446 ri
->prefix_len
== 0)
1449 if (ri
->prefix_len
== 0 &&
1450 !in6_dev
->cnf
.accept_ra_defrtr
)
1452 if (ri
->prefix_len
< in6_dev
->cnf
.accept_ra_rt_info_min_plen
)
1454 if (ri
->prefix_len
> in6_dev
->cnf
.accept_ra_rt_info_max_plen
)
1456 rt6_route_rcv(skb
->dev
, (u8
*)p
, (p
->nd_opt_len
) << 3,
1457 &ipv6_hdr(skb
)->saddr
);
1464 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1465 /* skip link-specific ndopts from interior routers */
1466 if (skb
->ndisc_nodetype
== NDISC_NODETYPE_NODEFAULT
) {
1468 "RA: %s, nodetype is NODEFAULT (interior routes), dev: %s\n",
1469 __func__
, skb
->dev
->name
);
1474 if (in6_dev
->cnf
.accept_ra_pinfo
&& ndopts
.nd_opts_pi
) {
1475 struct nd_opt_hdr
*p
;
1476 for (p
= ndopts
.nd_opts_pi
;
1478 p
= ndisc_next_option(p
, ndopts
.nd_opts_pi_end
)) {
1479 addrconf_prefix_rcv(skb
->dev
, (u8
*)p
,
1480 (p
->nd_opt_len
) << 3,
1481 ndopts
.nd_opts_src_lladdr
!= NULL
);
1485 if (ndopts
.nd_opts_mtu
&& in6_dev
->cnf
.accept_ra_mtu
) {
1489 memcpy(&n
, ((u8
*)(ndopts
.nd_opts_mtu
+1))+2, sizeof(mtu
));
1492 if (mtu
< IPV6_MIN_MTU
|| mtu
> skb
->dev
->mtu
) {
1493 ND_PRINTK(2, warn
, "RA: invalid mtu: %d\n", mtu
);
1494 } else if (in6_dev
->cnf
.mtu6
!= mtu
) {
1495 in6_dev
->cnf
.mtu6
= mtu
;
1496 fib6_metric_set(rt
, RTAX_MTU
, mtu
);
1497 rt6_mtu_change(skb
->dev
, mtu
);
1501 if (ndopts
.nd_useropts
) {
1502 struct nd_opt_hdr
*p
;
1503 for (p
= ndopts
.nd_useropts
;
1505 p
= ndisc_next_useropt(skb
->dev
, p
,
1506 ndopts
.nd_useropts_end
)) {
1507 ndisc_ra_useropt(skb
, p
);
1511 if (ndopts
.nd_opts_tgt_lladdr
|| ndopts
.nd_opts_rh
) {
1512 ND_PRINTK(2, warn
, "RA: invalid RA options\n");
1515 fib6_info_release(rt
);
1517 neigh_release(neigh
);
1520 static void ndisc_redirect_rcv(struct sk_buff
*skb
)
1523 struct ndisc_options ndopts
;
1524 struct rd_msg
*msg
= (struct rd_msg
*)skb_transport_header(skb
);
1525 u32 ndoptlen
= skb_tail_pointer(skb
) - (skb_transport_header(skb
) +
1526 offsetof(struct rd_msg
, opt
));
1528 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1529 switch (skb
->ndisc_nodetype
) {
1530 case NDISC_NODETYPE_HOST
:
1531 case NDISC_NODETYPE_NODEFAULT
:
1533 "Redirect: from host or unauthorized router\n");
1538 if (!(ipv6_addr_type(&ipv6_hdr(skb
)->saddr
) & IPV6_ADDR_LINKLOCAL
)) {
1540 "Redirect: source address is not link-local\n");
1544 if (!ndisc_parse_options(skb
->dev
, msg
->opt
, ndoptlen
, &ndopts
))
1547 if (!ndopts
.nd_opts_rh
) {
1548 ip6_redirect_no_header(skb
, dev_net(skb
->dev
),
1553 hdr
= (u8
*)ndopts
.nd_opts_rh
;
1555 if (!pskb_pull(skb
, hdr
- skb_transport_header(skb
)))
1558 icmpv6_notify(skb
, NDISC_REDIRECT
, 0, 0);
1561 static void ndisc_fill_redirect_hdr_option(struct sk_buff
*skb
,
1562 struct sk_buff
*orig_skb
,
1565 u8
*opt
= skb_put(skb
, rd_len
);
1568 *(opt
++) = ND_OPT_REDIRECT_HDR
;
1569 *(opt
++) = (rd_len
>> 3);
1572 skb_copy_bits(orig_skb
, skb_network_offset(orig_skb
), opt
,
1576 void ndisc_send_redirect(struct sk_buff
*skb
, const struct in6_addr
*target
)
1578 struct net_device
*dev
= skb
->dev
;
1579 struct net
*net
= dev_net(dev
);
1580 struct sock
*sk
= net
->ipv6
.ndisc_sk
;
1582 struct inet_peer
*peer
;
1583 struct sk_buff
*buff
;
1585 struct in6_addr saddr_buf
;
1586 struct rt6_info
*rt
;
1587 struct dst_entry
*dst
;
1590 u8 ha_buf
[MAX_ADDR_LEN
], *ha
= NULL
,
1591 ops_data_buf
[NDISC_OPS_REDIRECT_DATA_SPACE
], *ops_data
= NULL
;
1594 if (netif_is_l3_master(skb
->dev
)) {
1595 dev
= __dev_get_by_index(dev_net(skb
->dev
), IPCB(skb
)->iif
);
1600 if (ipv6_get_lladdr(dev
, &saddr_buf
, IFA_F_TENTATIVE
)) {
1601 ND_PRINTK(2, warn
, "Redirect: no link-local address on %s\n",
1606 if (!ipv6_addr_equal(&ipv6_hdr(skb
)->daddr
, target
) &&
1607 ipv6_addr_type(target
) != (IPV6_ADDR_UNICAST
|IPV6_ADDR_LINKLOCAL
)) {
1609 "Redirect: target address is not link-local unicast\n");
1613 icmpv6_flow_init(sk
, &fl6
, NDISC_REDIRECT
,
1614 &saddr_buf
, &ipv6_hdr(skb
)->saddr
, dev
->ifindex
);
1616 dst
= ip6_route_output(net
, NULL
, &fl6
);
1621 dst
= xfrm_lookup(net
, dst
, flowi6_to_flowi(&fl6
), NULL
, 0);
1625 rt
= (struct rt6_info
*) dst
;
1627 if (rt
->rt6i_flags
& RTF_GATEWAY
) {
1629 "Redirect: destination is not a neighbour\n");
1632 peer
= inet_getpeer_v6(net
->ipv6
.peers
, &ipv6_hdr(skb
)->saddr
, 1);
1633 ret
= inet_peer_xrlim_allow(peer
, 1*HZ
);
1639 if (dev
->addr_len
) {
1640 struct neighbour
*neigh
= dst_neigh_lookup(skb_dst(skb
), target
);
1643 "Redirect: no neigh for target address\n");
1647 read_lock_bh(&neigh
->lock
);
1648 if (neigh
->nud_state
& NUD_VALID
) {
1649 memcpy(ha_buf
, neigh
->ha
, dev
->addr_len
);
1650 read_unlock_bh(&neigh
->lock
);
1652 optlen
+= ndisc_redirect_opt_addr_space(dev
, neigh
,
1656 read_unlock_bh(&neigh
->lock
);
1658 neigh_release(neigh
);
1661 rd_len
= min_t(unsigned int,
1662 IPV6_MIN_MTU
- sizeof(struct ipv6hdr
) - sizeof(*msg
) - optlen
,
1667 buff
= ndisc_alloc_skb(dev
, sizeof(*msg
) + optlen
);
1671 msg
= skb_put(buff
, sizeof(*msg
));
1672 *msg
= (struct rd_msg
) {
1674 .icmp6_type
= NDISC_REDIRECT
,
1677 .dest
= ipv6_hdr(skb
)->daddr
,
1681 * include target_address option
1685 ndisc_fill_redirect_addr_option(buff
, ha
, ops_data
);
1688 * build redirect option and copy skb over to the new packet.
1692 ndisc_fill_redirect_hdr_option(buff
, skb
, rd_len
);
1694 skb_dst_set(buff
, dst
);
1695 ndisc_send_skb(buff
, &ipv6_hdr(skb
)->saddr
, &saddr_buf
);
1702 static void pndisc_redo(struct sk_buff
*skb
)
1708 static bool ndisc_suppress_frag_ndisc(struct sk_buff
*skb
)
1710 struct inet6_dev
*idev
= __in6_dev_get(skb
->dev
);
1714 if (IP6CB(skb
)->flags
& IP6SKB_FRAGMENTED
&&
1715 idev
->cnf
.suppress_frag_ndisc
) {
1716 net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n");
1722 int ndisc_rcv(struct sk_buff
*skb
)
1726 if (ndisc_suppress_frag_ndisc(skb
))
1729 if (skb_linearize(skb
))
1732 msg
= (struct nd_msg
*)skb_transport_header(skb
);
1734 __skb_push(skb
, skb
->data
- skb_transport_header(skb
));
1736 if (ipv6_hdr(skb
)->hop_limit
!= 255) {
1737 ND_PRINTK(2, warn
, "NDISC: invalid hop-limit: %d\n",
1738 ipv6_hdr(skb
)->hop_limit
);
1742 if (msg
->icmph
.icmp6_code
!= 0) {
1743 ND_PRINTK(2, warn
, "NDISC: invalid ICMPv6 code: %d\n",
1744 msg
->icmph
.icmp6_code
);
1748 switch (msg
->icmph
.icmp6_type
) {
1749 case NDISC_NEIGHBOUR_SOLICITATION
:
1750 memset(NEIGH_CB(skb
), 0, sizeof(struct neighbour_cb
));
1754 case NDISC_NEIGHBOUR_ADVERTISEMENT
:
1758 case NDISC_ROUTER_SOLICITATION
:
1762 case NDISC_ROUTER_ADVERTISEMENT
:
1763 ndisc_router_discovery(skb
);
1766 case NDISC_REDIRECT
:
1767 ndisc_redirect_rcv(skb
);
1774 static int ndisc_netdev_event(struct notifier_block
*this, unsigned long event
, void *ptr
)
1776 struct net_device
*dev
= netdev_notifier_info_to_dev(ptr
);
1777 struct netdev_notifier_change_info
*change_info
;
1778 struct net
*net
= dev_net(dev
);
1779 struct inet6_dev
*idev
;
1782 case NETDEV_CHANGEADDR
:
1783 neigh_changeaddr(&nd_tbl
, dev
);
1784 fib6_run_gc(0, net
, false);
1787 idev
= in6_dev_get(dev
);
1790 if (idev
->cnf
.ndisc_notify
||
1791 net
->ipv6
.devconf_all
->ndisc_notify
)
1792 ndisc_send_unsol_na(dev
);
1797 if (change_info
->flags_changed
& IFF_NOARP
)
1798 neigh_changeaddr(&nd_tbl
, dev
);
1799 if (!netif_carrier_ok(dev
))
1800 neigh_carrier_down(&nd_tbl
, dev
);
1803 neigh_ifdown(&nd_tbl
, dev
);
1804 fib6_run_gc(0, net
, false);
1806 case NETDEV_NOTIFY_PEERS
:
1807 ndisc_send_unsol_na(dev
);
1816 static struct notifier_block ndisc_netdev_notifier
= {
1817 .notifier_call
= ndisc_netdev_event
,
1818 .priority
= ADDRCONF_NOTIFY_PRIORITY
- 5,
1821 #ifdef CONFIG_SYSCTL
1822 static void ndisc_warn_deprecated_sysctl(struct ctl_table
*ctl
,
1823 const char *func
, const char *dev_name
)
1825 static char warncomm
[TASK_COMM_LEN
];
1827 if (strcmp(warncomm
, current
->comm
) && warned
< 5) {
1828 strcpy(warncomm
, current
->comm
);
1829 pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n",
1831 dev_name
, ctl
->procname
,
1832 dev_name
, ctl
->procname
);
1837 int ndisc_ifinfo_sysctl_change(struct ctl_table
*ctl
, int write
, void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1839 struct net_device
*dev
= ctl
->extra1
;
1840 struct inet6_dev
*idev
;
1843 if ((strcmp(ctl
->procname
, "retrans_time") == 0) ||
1844 (strcmp(ctl
->procname
, "base_reachable_time") == 0))
1845 ndisc_warn_deprecated_sysctl(ctl
, "syscall", dev
? dev
->name
: "default");
1847 if (strcmp(ctl
->procname
, "retrans_time") == 0)
1848 ret
= neigh_proc_dointvec(ctl
, write
, buffer
, lenp
, ppos
);
1850 else if (strcmp(ctl
->procname
, "base_reachable_time") == 0)
1851 ret
= neigh_proc_dointvec_jiffies(ctl
, write
,
1852 buffer
, lenp
, ppos
);
1854 else if ((strcmp(ctl
->procname
, "retrans_time_ms") == 0) ||
1855 (strcmp(ctl
->procname
, "base_reachable_time_ms") == 0))
1856 ret
= neigh_proc_dointvec_ms_jiffies(ctl
, write
,
1857 buffer
, lenp
, ppos
);
1861 if (write
&& ret
== 0 && dev
&& (idev
= in6_dev_get(dev
)) != NULL
) {
1862 if (ctl
->data
== &NEIGH_VAR(idev
->nd_parms
, BASE_REACHABLE_TIME
))
1863 idev
->nd_parms
->reachable_time
=
1864 neigh_rand_reach_time(NEIGH_VAR(idev
->nd_parms
, BASE_REACHABLE_TIME
));
1865 idev
->tstamp
= jiffies
;
1866 inet6_ifinfo_notify(RTM_NEWLINK
, idev
);
1875 static int __net_init
ndisc_net_init(struct net
*net
)
1877 struct ipv6_pinfo
*np
;
1881 err
= inet_ctl_sock_create(&sk
, PF_INET6
,
1882 SOCK_RAW
, IPPROTO_ICMPV6
, net
);
1885 "NDISC: Failed to initialize the control socket (err %d)\n",
1890 net
->ipv6
.ndisc_sk
= sk
;
1893 np
->hop_limit
= 255;
1894 /* Do not loopback ndisc messages */
1900 static void __net_exit
ndisc_net_exit(struct net
*net
)
1902 inet_ctl_sock_destroy(net
->ipv6
.ndisc_sk
);
1905 static struct pernet_operations ndisc_net_ops
= {
1906 .init
= ndisc_net_init
,
1907 .exit
= ndisc_net_exit
,
1910 int __init
ndisc_init(void)
1914 err
= register_pernet_subsys(&ndisc_net_ops
);
1918 * Initialize the neighbour table
1920 neigh_table_init(NEIGH_ND_TABLE
, &nd_tbl
);
1922 #ifdef CONFIG_SYSCTL
1923 err
= neigh_sysctl_register(NULL
, &nd_tbl
.parms
,
1924 ndisc_ifinfo_sysctl_change
);
1926 goto out_unregister_pernet
;
1931 #ifdef CONFIG_SYSCTL
1932 out_unregister_pernet
:
1933 unregister_pernet_subsys(&ndisc_net_ops
);
1938 int __init
ndisc_late_init(void)
1940 return register_netdevice_notifier(&ndisc_netdev_notifier
);
1943 void ndisc_late_cleanup(void)
1945 unregister_netdevice_notifier(&ndisc_netdev_notifier
);
1948 void ndisc_cleanup(void)
1950 #ifdef CONFIG_SYSCTL
1951 neigh_sysctl_unregister(&nd_tbl
.parms
);
1953 neigh_table_clear(NEIGH_ND_TABLE
, &nd_tbl
);
1954 unregister_pernet_subsys(&ndisc_net_ops
);