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 opt
->nd_opt_type
== ND_OPT_PREF64
||
201 ndisc_ops_is_useropt(dev
, opt
->nd_opt_type
);
204 static struct nd_opt_hdr
*ndisc_next_useropt(const struct net_device
*dev
,
205 struct nd_opt_hdr
*cur
,
206 struct nd_opt_hdr
*end
)
208 if (!cur
|| !end
|| cur
>= end
)
211 cur
= ((void *)cur
) + (cur
->nd_opt_len
<< 3);
212 } while (cur
< end
&& !ndisc_is_useropt(dev
, cur
));
213 return cur
<= end
&& ndisc_is_useropt(dev
, cur
) ? cur
: NULL
;
216 struct ndisc_options
*ndisc_parse_options(const struct net_device
*dev
,
217 u8
*opt
, int opt_len
,
218 struct ndisc_options
*ndopts
)
220 struct nd_opt_hdr
*nd_opt
= (struct nd_opt_hdr
*)opt
;
222 if (!nd_opt
|| opt_len
< 0 || !ndopts
)
224 memset(ndopts
, 0, sizeof(*ndopts
));
227 if (opt_len
< sizeof(struct nd_opt_hdr
))
229 l
= nd_opt
->nd_opt_len
<< 3;
230 if (opt_len
< l
|| l
== 0)
232 if (ndisc_ops_parse_options(dev
, nd_opt
, ndopts
))
234 switch (nd_opt
->nd_opt_type
) {
235 case ND_OPT_SOURCE_LL_ADDR
:
236 case ND_OPT_TARGET_LL_ADDR
:
239 case ND_OPT_REDIRECT_HDR
:
240 if (ndopts
->nd_opt_array
[nd_opt
->nd_opt_type
]) {
242 "%s: duplicated ND6 option found: type=%d\n",
243 __func__
, nd_opt
->nd_opt_type
);
245 ndopts
->nd_opt_array
[nd_opt
->nd_opt_type
] = nd_opt
;
248 case ND_OPT_PREFIX_INFO
:
249 ndopts
->nd_opts_pi_end
= nd_opt
;
250 if (!ndopts
->nd_opt_array
[nd_opt
->nd_opt_type
])
251 ndopts
->nd_opt_array
[nd_opt
->nd_opt_type
] = nd_opt
;
253 #ifdef CONFIG_IPV6_ROUTE_INFO
254 case ND_OPT_ROUTE_INFO
:
255 ndopts
->nd_opts_ri_end
= nd_opt
;
256 if (!ndopts
->nd_opts_ri
)
257 ndopts
->nd_opts_ri
= nd_opt
;
261 if (ndisc_is_useropt(dev
, nd_opt
)) {
262 ndopts
->nd_useropts_end
= nd_opt
;
263 if (!ndopts
->nd_useropts
)
264 ndopts
->nd_useropts
= nd_opt
;
267 * Unknown options must be silently ignored,
268 * to accommodate future extension to the
272 "%s: ignored unsupported option; type=%d, len=%d\n",
280 nd_opt
= ((void *)nd_opt
) + l
;
285 int ndisc_mc_map(const struct in6_addr
*addr
, char *buf
, struct net_device
*dev
, int dir
)
289 case ARPHRD_IEEE802
: /* Not sure. Check it later. --ANK */
291 ipv6_eth_mc_map(addr
, buf
);
294 ipv6_arcnet_mc_map(addr
, buf
);
296 case ARPHRD_INFINIBAND
:
297 ipv6_ib_mc_map(addr
, dev
->broadcast
, buf
);
300 return ipv6_ipgre_mc_map(addr
, dev
->broadcast
, buf
);
303 memcpy(buf
, dev
->broadcast
, dev
->addr_len
);
309 EXPORT_SYMBOL(ndisc_mc_map
);
311 static u32
ndisc_hash(const void *pkey
,
312 const struct net_device
*dev
,
315 return ndisc_hashfn(pkey
, dev
, hash_rnd
);
318 static bool ndisc_key_eq(const struct neighbour
*n
, const void *pkey
)
320 return neigh_key_eq128(n
, pkey
);
323 static int ndisc_constructor(struct neighbour
*neigh
)
325 struct in6_addr
*addr
= (struct in6_addr
*)&neigh
->primary_key
;
326 struct net_device
*dev
= neigh
->dev
;
327 struct inet6_dev
*in6_dev
;
328 struct neigh_parms
*parms
;
329 bool is_multicast
= ipv6_addr_is_multicast(addr
);
331 in6_dev
= in6_dev_get(dev
);
336 parms
= in6_dev
->nd_parms
;
337 __neigh_parms_put(neigh
->parms
);
338 neigh
->parms
= neigh_parms_clone(parms
);
340 neigh
->type
= is_multicast
? RTN_MULTICAST
: RTN_UNICAST
;
341 if (!dev
->header_ops
) {
342 neigh
->nud_state
= NUD_NOARP
;
343 neigh
->ops
= &ndisc_direct_ops
;
344 neigh
->output
= neigh_direct_output
;
347 neigh
->nud_state
= NUD_NOARP
;
348 ndisc_mc_map(addr
, neigh
->ha
, dev
, 1);
349 } else if (dev
->flags
&(IFF_NOARP
|IFF_LOOPBACK
)) {
350 neigh
->nud_state
= NUD_NOARP
;
351 memcpy(neigh
->ha
, dev
->dev_addr
, dev
->addr_len
);
352 if (dev
->flags
&IFF_LOOPBACK
)
353 neigh
->type
= RTN_LOCAL
;
354 } else if (dev
->flags
&IFF_POINTOPOINT
) {
355 neigh
->nud_state
= NUD_NOARP
;
356 memcpy(neigh
->ha
, dev
->broadcast
, dev
->addr_len
);
358 if (dev
->header_ops
->cache
)
359 neigh
->ops
= &ndisc_hh_ops
;
361 neigh
->ops
= &ndisc_generic_ops
;
362 if (neigh
->nud_state
&NUD_VALID
)
363 neigh
->output
= neigh
->ops
->connected_output
;
365 neigh
->output
= neigh
->ops
->output
;
367 in6_dev_put(in6_dev
);
371 static int pndisc_constructor(struct pneigh_entry
*n
)
373 struct in6_addr
*addr
= (struct in6_addr
*)&n
->key
;
374 struct in6_addr maddr
;
375 struct net_device
*dev
= n
->dev
;
377 if (!dev
|| !__in6_dev_get(dev
))
379 addrconf_addr_solict_mult(addr
, &maddr
);
380 ipv6_dev_mc_inc(dev
, &maddr
);
384 static void pndisc_destructor(struct pneigh_entry
*n
)
386 struct in6_addr
*addr
= (struct in6_addr
*)&n
->key
;
387 struct in6_addr maddr
;
388 struct net_device
*dev
= n
->dev
;
390 if (!dev
|| !__in6_dev_get(dev
))
392 addrconf_addr_solict_mult(addr
, &maddr
);
393 ipv6_dev_mc_dec(dev
, &maddr
);
396 /* called with rtnl held */
397 static bool ndisc_allow_add(const struct net_device
*dev
,
398 struct netlink_ext_ack
*extack
)
400 struct inet6_dev
*idev
= __in6_dev_get(dev
);
402 if (!idev
|| idev
->cnf
.disable_ipv6
) {
403 NL_SET_ERR_MSG(extack
, "IPv6 is disabled on this device");
410 static struct sk_buff
*ndisc_alloc_skb(struct net_device
*dev
,
413 int hlen
= LL_RESERVED_SPACE(dev
);
414 int tlen
= dev
->needed_tailroom
;
415 struct sock
*sk
= dev_net(dev
)->ipv6
.ndisc_sk
;
418 skb
= alloc_skb(hlen
+ sizeof(struct ipv6hdr
) + len
+ tlen
, GFP_ATOMIC
);
420 ND_PRINTK(0, err
, "ndisc: %s failed to allocate an skb\n",
425 skb
->protocol
= htons(ETH_P_IPV6
);
428 skb_reserve(skb
, hlen
+ sizeof(struct ipv6hdr
));
429 skb_reset_transport_header(skb
);
431 /* Manually assign socket ownership as we avoid calling
432 * sock_alloc_send_pskb() to bypass wmem buffer limits
434 skb_set_owner_w(skb
, sk
);
439 static void ip6_nd_hdr(struct sk_buff
*skb
,
440 const struct in6_addr
*saddr
,
441 const struct in6_addr
*daddr
,
442 int hop_limit
, int len
)
445 struct inet6_dev
*idev
;
449 idev
= __in6_dev_get(skb
->dev
);
450 tclass
= idev
? idev
->cnf
.ndisc_tclass
: 0;
453 skb_push(skb
, sizeof(*hdr
));
454 skb_reset_network_header(skb
);
457 ip6_flow_hdr(hdr
, tclass
, 0);
459 hdr
->payload_len
= htons(len
);
460 hdr
->nexthdr
= IPPROTO_ICMPV6
;
461 hdr
->hop_limit
= hop_limit
;
467 static void ndisc_send_skb(struct sk_buff
*skb
,
468 const struct in6_addr
*daddr
,
469 const struct in6_addr
*saddr
)
471 struct dst_entry
*dst
= skb_dst(skb
);
472 struct net
*net
= dev_net(skb
->dev
);
473 struct sock
*sk
= net
->ipv6
.ndisc_sk
;
474 struct inet6_dev
*idev
;
476 struct icmp6hdr
*icmp6h
= icmp6_hdr(skb
);
479 type
= icmp6h
->icmp6_type
;
483 int oif
= skb
->dev
->ifindex
;
485 icmpv6_flow_init(sk
, &fl6
, type
, saddr
, daddr
, oif
);
486 dst
= icmp6_dst_alloc(skb
->dev
, &fl6
);
492 skb_dst_set(skb
, dst
);
495 icmp6h
->icmp6_cksum
= csum_ipv6_magic(saddr
, daddr
, skb
->len
,
500 ip6_nd_hdr(skb
, saddr
, daddr
, inet6_sk(sk
)->hop_limit
, skb
->len
);
503 idev
= __in6_dev_get(dst
->dev
);
504 IP6_UPD_PO_STATS(net
, idev
, IPSTATS_MIB_OUT
, skb
->len
);
506 err
= NF_HOOK(NFPROTO_IPV6
, NF_INET_LOCAL_OUT
,
507 net
, sk
, skb
, NULL
, dst
->dev
,
510 ICMP6MSGOUT_INC_STATS(net
, idev
, type
);
511 ICMP6_INC_STATS(net
, idev
, ICMP6_MIB_OUTMSGS
);
517 void ndisc_send_na(struct net_device
*dev
, const struct in6_addr
*daddr
,
518 const struct in6_addr
*solicited_addr
,
519 bool router
, bool solicited
, bool override
, bool inc_opt
)
522 struct in6_addr tmpaddr
;
523 struct inet6_ifaddr
*ifp
;
524 const struct in6_addr
*src_addr
;
528 /* for anycast or proxy, solicited_addr != src_addr */
529 ifp
= ipv6_get_ifaddr(dev_net(dev
), solicited_addr
, dev
, 1);
531 src_addr
= solicited_addr
;
532 if (ifp
->flags
& IFA_F_OPTIMISTIC
)
534 inc_opt
|= ifp
->idev
->cnf
.force_tllao
;
537 if (ipv6_dev_get_saddr(dev_net(dev
), dev
, daddr
,
538 inet6_sk(dev_net(dev
)->ipv6
.ndisc_sk
)->srcprefs
,
547 optlen
+= ndisc_opt_addr_space(dev
,
548 NDISC_NEIGHBOUR_ADVERTISEMENT
);
550 skb
= ndisc_alloc_skb(dev
, sizeof(*msg
) + optlen
);
554 msg
= skb_put(skb
, sizeof(*msg
));
555 *msg
= (struct nd_msg
) {
557 .icmp6_type
= NDISC_NEIGHBOUR_ADVERTISEMENT
,
558 .icmp6_router
= router
,
559 .icmp6_solicited
= solicited
,
560 .icmp6_override
= override
,
562 .target
= *solicited_addr
,
566 ndisc_fill_addr_option(skb
, ND_OPT_TARGET_LL_ADDR
,
568 NDISC_NEIGHBOUR_ADVERTISEMENT
);
570 ndisc_send_skb(skb
, daddr
, src_addr
);
573 static void ndisc_send_unsol_na(struct net_device
*dev
)
575 struct inet6_dev
*idev
;
576 struct inet6_ifaddr
*ifa
;
578 idev
= in6_dev_get(dev
);
582 read_lock_bh(&idev
->lock
);
583 list_for_each_entry(ifa
, &idev
->addr_list
, if_list
) {
584 /* skip tentative addresses until dad completes */
585 if (ifa
->flags
& IFA_F_TENTATIVE
&&
586 !(ifa
->flags
& IFA_F_OPTIMISTIC
))
589 ndisc_send_na(dev
, &in6addr_linklocal_allnodes
, &ifa
->addr
,
590 /*router=*/ !!idev
->cnf
.forwarding
,
591 /*solicited=*/ false, /*override=*/ true,
594 read_unlock_bh(&idev
->lock
);
599 void ndisc_send_ns(struct net_device
*dev
, const struct in6_addr
*solicit
,
600 const struct in6_addr
*daddr
, const struct in6_addr
*saddr
,
604 struct in6_addr addr_buf
;
605 int inc_opt
= dev
->addr_len
;
610 if (ipv6_get_lladdr(dev
, &addr_buf
,
611 (IFA_F_TENTATIVE
|IFA_F_OPTIMISTIC
)))
616 if (ipv6_addr_any(saddr
))
619 optlen
+= ndisc_opt_addr_space(dev
,
620 NDISC_NEIGHBOUR_SOLICITATION
);
624 skb
= ndisc_alloc_skb(dev
, sizeof(*msg
) + optlen
);
628 msg
= skb_put(skb
, sizeof(*msg
));
629 *msg
= (struct nd_msg
) {
631 .icmp6_type
= NDISC_NEIGHBOUR_SOLICITATION
,
637 ndisc_fill_addr_option(skb
, ND_OPT_SOURCE_LL_ADDR
,
639 NDISC_NEIGHBOUR_SOLICITATION
);
641 u8
*opt
= skb_put(skb
, 8);
643 opt
[0] = ND_OPT_NONCE
;
645 memcpy(opt
+ 2, &nonce
, 6);
648 ndisc_send_skb(skb
, daddr
, saddr
);
651 void ndisc_send_rs(struct net_device
*dev
, const struct in6_addr
*saddr
,
652 const struct in6_addr
*daddr
)
656 int send_sllao
= dev
->addr_len
;
659 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
661 * According to section 2.2 of RFC 4429, we must not
662 * send router solicitations with a sllao from
663 * optimistic addresses, but we may send the solicitation
664 * if we don't include the sllao. So here we check
665 * if our address is optimistic, and if so, we
666 * suppress the inclusion of the sllao.
669 struct inet6_ifaddr
*ifp
= ipv6_get_ifaddr(dev_net(dev
), saddr
,
672 if (ifp
->flags
& IFA_F_OPTIMISTIC
) {
682 optlen
+= ndisc_opt_addr_space(dev
, NDISC_ROUTER_SOLICITATION
);
684 skb
= ndisc_alloc_skb(dev
, sizeof(*msg
) + optlen
);
688 msg
= skb_put(skb
, sizeof(*msg
));
689 *msg
= (struct rs_msg
) {
691 .icmp6_type
= NDISC_ROUTER_SOLICITATION
,
696 ndisc_fill_addr_option(skb
, ND_OPT_SOURCE_LL_ADDR
,
698 NDISC_ROUTER_SOLICITATION
);
700 ndisc_send_skb(skb
, daddr
, saddr
);
704 static void ndisc_error_report(struct neighbour
*neigh
, struct sk_buff
*skb
)
707 * "The sender MUST return an ICMP
708 * destination unreachable"
710 dst_link_failure(skb
);
714 /* Called with locked neigh: either read or both */
716 static void ndisc_solicit(struct neighbour
*neigh
, struct sk_buff
*skb
)
718 struct in6_addr
*saddr
= NULL
;
719 struct in6_addr mcaddr
;
720 struct net_device
*dev
= neigh
->dev
;
721 struct in6_addr
*target
= (struct in6_addr
*)&neigh
->primary_key
;
722 int probes
= atomic_read(&neigh
->probes
);
724 if (skb
&& ipv6_chk_addr_and_flags(dev_net(dev
), &ipv6_hdr(skb
)->saddr
,
726 IFA_F_TENTATIVE
|IFA_F_OPTIMISTIC
))
727 saddr
= &ipv6_hdr(skb
)->saddr
;
728 probes
-= NEIGH_VAR(neigh
->parms
, UCAST_PROBES
);
730 if (!(neigh
->nud_state
& NUD_VALID
)) {
732 "%s: trying to ucast probe in NUD_INVALID: %pI6\n",
735 ndisc_send_ns(dev
, target
, target
, saddr
, 0);
736 } else if ((probes
-= NEIGH_VAR(neigh
->parms
, APP_PROBES
)) < 0) {
739 addrconf_addr_solict_mult(target
, &mcaddr
);
740 ndisc_send_ns(dev
, target
, &mcaddr
, saddr
, 0);
744 static int pndisc_is_router(const void *pkey
,
745 struct net_device
*dev
)
747 struct pneigh_entry
*n
;
750 read_lock_bh(&nd_tbl
.lock
);
751 n
= __pneigh_lookup(&nd_tbl
, dev_net(dev
), pkey
, dev
);
753 ret
= !!(n
->flags
& NTF_ROUTER
);
754 read_unlock_bh(&nd_tbl
.lock
);
759 void ndisc_update(const struct net_device
*dev
, struct neighbour
*neigh
,
760 const u8
*lladdr
, u8
new, u32 flags
, u8 icmp6_type
,
761 struct ndisc_options
*ndopts
)
763 neigh_update(neigh
, lladdr
, new, flags
, 0);
764 /* report ndisc ops about neighbour update */
765 ndisc_ops_update(dev
, neigh
, flags
, icmp6_type
, ndopts
);
768 static void ndisc_recv_ns(struct sk_buff
*skb
)
770 struct nd_msg
*msg
= (struct nd_msg
*)skb_transport_header(skb
);
771 const struct in6_addr
*saddr
= &ipv6_hdr(skb
)->saddr
;
772 const struct in6_addr
*daddr
= &ipv6_hdr(skb
)->daddr
;
774 u32 ndoptlen
= skb_tail_pointer(skb
) - (skb_transport_header(skb
) +
775 offsetof(struct nd_msg
, opt
));
776 struct ndisc_options ndopts
;
777 struct net_device
*dev
= skb
->dev
;
778 struct inet6_ifaddr
*ifp
;
779 struct inet6_dev
*idev
= NULL
;
780 struct neighbour
*neigh
;
781 int dad
= ipv6_addr_any(saddr
);
786 if (skb
->len
< sizeof(struct nd_msg
)) {
787 ND_PRINTK(2, warn
, "NS: packet too short\n");
791 if (ipv6_addr_is_multicast(&msg
->target
)) {
792 ND_PRINTK(2, warn
, "NS: multicast target address\n");
798 * DAD has to be destined for solicited node multicast address.
800 if (dad
&& !ipv6_addr_is_solict_mult(daddr
)) {
801 ND_PRINTK(2, warn
, "NS: bad DAD packet (wrong destination)\n");
805 if (!ndisc_parse_options(dev
, msg
->opt
, ndoptlen
, &ndopts
)) {
806 ND_PRINTK(2, warn
, "NS: invalid ND options\n");
810 if (ndopts
.nd_opts_src_lladdr
) {
811 lladdr
= ndisc_opt_addr_data(ndopts
.nd_opts_src_lladdr
, dev
);
814 "NS: invalid link-layer address length\n");
819 * If the IP source address is the unspecified address,
820 * there MUST NOT be source link-layer address option
825 "NS: bad DAD packet (link-layer address option)\n");
829 if (ndopts
.nd_opts_nonce
&& ndopts
.nd_opts_nonce
->nd_opt_len
== 1)
830 memcpy(&nonce
, (u8
*)(ndopts
.nd_opts_nonce
+ 1), 6);
832 inc
= ipv6_addr_is_multicast(daddr
);
834 ifp
= ipv6_get_ifaddr(dev_net(dev
), &msg
->target
, dev
, 1);
837 if (ifp
->flags
& (IFA_F_TENTATIVE
|IFA_F_OPTIMISTIC
)) {
839 if (nonce
!= 0 && ifp
->dad_nonce
== nonce
) {
840 u8
*np
= (u8
*)&nonce
;
841 /* Matching nonce if looped back */
843 "%s: IPv6 DAD loopback for address %pI6c nonce %pM ignored\n",
844 ifp
->idev
->dev
->name
,
849 * We are colliding with another node
851 * so fail our DAD process
853 addrconf_dad_failure(skb
, ifp
);
857 * This is not a dad solicitation.
858 * If we are an optimistic node,
860 * Otherwise, we should ignore it.
862 if (!(ifp
->flags
& IFA_F_OPTIMISTIC
))
869 struct net
*net
= dev_net(dev
);
871 /* perhaps an address on the master device */
872 if (netif_is_l3_slave(dev
)) {
873 struct net_device
*mdev
;
875 mdev
= netdev_master_upper_dev_get_rcu(dev
);
877 ifp
= ipv6_get_ifaddr(net
, &msg
->target
, mdev
, 1);
883 idev
= in6_dev_get(dev
);
885 /* XXX: count this drop? */
889 if (ipv6_chk_acast_addr(net
, dev
, &msg
->target
) ||
890 (idev
->cnf
.forwarding
&&
891 (net
->ipv6
.devconf_all
->proxy_ndp
|| idev
->cnf
.proxy_ndp
) &&
892 (is_router
= pndisc_is_router(&msg
->target
, dev
)) >= 0)) {
893 if (!(NEIGH_CB(skb
)->flags
& LOCALLY_ENQUEUED
) &&
894 skb
->pkt_type
!= PACKET_HOST
&&
896 NEIGH_VAR(idev
->nd_parms
, PROXY_DELAY
) != 0) {
898 * for anycast or proxy,
899 * sender should delay its response
900 * by a random time between 0 and
901 * MAX_ANYCAST_DELAY_TIME seconds.
902 * (RFC2461) -- yoshfuji
904 struct sk_buff
*n
= skb_clone(skb
, GFP_ATOMIC
);
906 pneigh_enqueue(&nd_tbl
, idev
->nd_parms
, n
);
914 is_router
= idev
->cnf
.forwarding
;
917 ndisc_send_na(dev
, &in6addr_linklocal_allnodes
, &msg
->target
,
918 !!is_router
, false, (ifp
!= NULL
), true);
923 NEIGH_CACHE_STAT_INC(&nd_tbl
, rcv_probes_mcast
);
925 NEIGH_CACHE_STAT_INC(&nd_tbl
, rcv_probes_ucast
);
928 * update / create cache entry
929 * for the source address
931 neigh
= __neigh_lookup(&nd_tbl
, saddr
, dev
,
932 !inc
|| lladdr
|| !dev
->addr_len
);
934 ndisc_update(dev
, neigh
, lladdr
, NUD_STALE
,
935 NEIGH_UPDATE_F_WEAK_OVERRIDE
|
936 NEIGH_UPDATE_F_OVERRIDE
,
937 NDISC_NEIGHBOUR_SOLICITATION
, &ndopts
);
938 if (neigh
|| !dev
->header_ops
) {
939 ndisc_send_na(dev
, saddr
, &msg
->target
, !!is_router
,
940 true, (ifp
!= NULL
&& inc
), inc
);
942 neigh_release(neigh
);
952 static void ndisc_recv_na(struct sk_buff
*skb
)
954 struct nd_msg
*msg
= (struct nd_msg
*)skb_transport_header(skb
);
955 struct in6_addr
*saddr
= &ipv6_hdr(skb
)->saddr
;
956 const struct in6_addr
*daddr
= &ipv6_hdr(skb
)->daddr
;
958 u32 ndoptlen
= skb_tail_pointer(skb
) - (skb_transport_header(skb
) +
959 offsetof(struct nd_msg
, opt
));
960 struct ndisc_options ndopts
;
961 struct net_device
*dev
= skb
->dev
;
962 struct inet6_dev
*idev
= __in6_dev_get(dev
);
963 struct inet6_ifaddr
*ifp
;
964 struct neighbour
*neigh
;
966 if (skb
->len
< sizeof(struct nd_msg
)) {
967 ND_PRINTK(2, warn
, "NA: packet too short\n");
971 if (ipv6_addr_is_multicast(&msg
->target
)) {
972 ND_PRINTK(2, warn
, "NA: target address is multicast\n");
976 if (ipv6_addr_is_multicast(daddr
) &&
977 msg
->icmph
.icmp6_solicited
) {
978 ND_PRINTK(2, warn
, "NA: solicited NA is multicasted\n");
982 /* For some 802.11 wireless deployments (and possibly other networks),
983 * there will be a NA proxy and unsolicitd packets are attacks
984 * and thus should not be accepted.
986 if (!msg
->icmph
.icmp6_solicited
&& idev
&&
987 idev
->cnf
.drop_unsolicited_na
)
990 if (!ndisc_parse_options(dev
, msg
->opt
, ndoptlen
, &ndopts
)) {
991 ND_PRINTK(2, warn
, "NS: invalid ND option\n");
994 if (ndopts
.nd_opts_tgt_lladdr
) {
995 lladdr
= ndisc_opt_addr_data(ndopts
.nd_opts_tgt_lladdr
, dev
);
998 "NA: invalid link-layer address length\n");
1002 ifp
= ipv6_get_ifaddr(dev_net(dev
), &msg
->target
, dev
, 1);
1004 if (skb
->pkt_type
!= PACKET_LOOPBACK
1005 && (ifp
->flags
& IFA_F_TENTATIVE
)) {
1006 addrconf_dad_failure(skb
, ifp
);
1009 /* What should we make now? The advertisement
1010 is invalid, but ndisc specs say nothing
1011 about it. It could be misconfiguration, or
1012 an smart proxy agent tries to help us :-)
1014 We should not print the error if NA has been
1015 received from loopback - it is just our own
1016 unsolicited advertisement.
1018 if (skb
->pkt_type
!= PACKET_LOOPBACK
)
1020 "NA: %pM advertised our address %pI6c on %s!\n",
1021 eth_hdr(skb
)->h_source
, &ifp
->addr
, ifp
->idev
->dev
->name
);
1025 neigh
= neigh_lookup(&nd_tbl
, &msg
->target
, dev
);
1028 u8 old_flags
= neigh
->flags
;
1029 struct net
*net
= dev_net(dev
);
1031 if (neigh
->nud_state
& NUD_FAILED
)
1035 * Don't update the neighbor cache entry on a proxy NA from
1036 * ourselves because either the proxied node is off link or it
1037 * has already sent a NA to us.
1039 if (lladdr
&& !memcmp(lladdr
, dev
->dev_addr
, dev
->addr_len
) &&
1040 net
->ipv6
.devconf_all
->forwarding
&& net
->ipv6
.devconf_all
->proxy_ndp
&&
1041 pneigh_lookup(&nd_tbl
, net
, &msg
->target
, dev
, 0)) {
1042 /* XXX: idev->cnf.proxy_ndp */
1046 ndisc_update(dev
, neigh
, lladdr
,
1047 msg
->icmph
.icmp6_solicited
? NUD_REACHABLE
: NUD_STALE
,
1048 NEIGH_UPDATE_F_WEAK_OVERRIDE
|
1049 (msg
->icmph
.icmp6_override
? NEIGH_UPDATE_F_OVERRIDE
: 0)|
1050 NEIGH_UPDATE_F_OVERRIDE_ISROUTER
|
1051 (msg
->icmph
.icmp6_router
? NEIGH_UPDATE_F_ISROUTER
: 0),
1052 NDISC_NEIGHBOUR_ADVERTISEMENT
, &ndopts
);
1054 if ((old_flags
& ~neigh
->flags
) & NTF_ROUTER
) {
1056 * Change: router to host
1058 rt6_clean_tohost(dev_net(dev
), saddr
);
1062 neigh_release(neigh
);
1066 static void ndisc_recv_rs(struct sk_buff
*skb
)
1068 struct rs_msg
*rs_msg
= (struct rs_msg
*)skb_transport_header(skb
);
1069 unsigned long ndoptlen
= skb
->len
- sizeof(*rs_msg
);
1070 struct neighbour
*neigh
;
1071 struct inet6_dev
*idev
;
1072 const struct in6_addr
*saddr
= &ipv6_hdr(skb
)->saddr
;
1073 struct ndisc_options ndopts
;
1076 if (skb
->len
< sizeof(*rs_msg
))
1079 idev
= __in6_dev_get(skb
->dev
);
1081 ND_PRINTK(1, err
, "RS: can't find in6 device\n");
1085 /* Don't accept RS if we're not in router mode */
1086 if (!idev
->cnf
.forwarding
)
1090 * Don't update NCE if src = ::;
1091 * this implies that the source node has no ip address assigned yet.
1093 if (ipv6_addr_any(saddr
))
1096 /* Parse ND options */
1097 if (!ndisc_parse_options(skb
->dev
, rs_msg
->opt
, ndoptlen
, &ndopts
)) {
1098 ND_PRINTK(2, notice
, "NS: invalid ND option, ignored\n");
1102 if (ndopts
.nd_opts_src_lladdr
) {
1103 lladdr
= ndisc_opt_addr_data(ndopts
.nd_opts_src_lladdr
,
1109 neigh
= __neigh_lookup(&nd_tbl
, saddr
, skb
->dev
, 1);
1111 ndisc_update(skb
->dev
, neigh
, lladdr
, NUD_STALE
,
1112 NEIGH_UPDATE_F_WEAK_OVERRIDE
|
1113 NEIGH_UPDATE_F_OVERRIDE
|
1114 NEIGH_UPDATE_F_OVERRIDE_ISROUTER
,
1115 NDISC_ROUTER_SOLICITATION
, &ndopts
);
1116 neigh_release(neigh
);
1122 static void ndisc_ra_useropt(struct sk_buff
*ra
, struct nd_opt_hdr
*opt
)
1124 struct icmp6hdr
*icmp6h
= (struct icmp6hdr
*)skb_transport_header(ra
);
1125 struct sk_buff
*skb
;
1126 struct nlmsghdr
*nlh
;
1127 struct nduseroptmsg
*ndmsg
;
1128 struct net
*net
= dev_net(ra
->dev
);
1130 int base_size
= NLMSG_ALIGN(sizeof(struct nduseroptmsg
)
1131 + (opt
->nd_opt_len
<< 3));
1132 size_t msg_size
= base_size
+ nla_total_size(sizeof(struct in6_addr
));
1134 skb
= nlmsg_new(msg_size
, GFP_ATOMIC
);
1140 nlh
= nlmsg_put(skb
, 0, 0, RTM_NEWNDUSEROPT
, base_size
, 0);
1142 goto nla_put_failure
;
1145 ndmsg
= nlmsg_data(nlh
);
1146 ndmsg
->nduseropt_family
= AF_INET6
;
1147 ndmsg
->nduseropt_ifindex
= ra
->dev
->ifindex
;
1148 ndmsg
->nduseropt_icmp_type
= icmp6h
->icmp6_type
;
1149 ndmsg
->nduseropt_icmp_code
= icmp6h
->icmp6_code
;
1150 ndmsg
->nduseropt_opts_len
= opt
->nd_opt_len
<< 3;
1152 memcpy(ndmsg
+ 1, opt
, opt
->nd_opt_len
<< 3);
1154 if (nla_put_in6_addr(skb
, NDUSEROPT_SRCADDR
, &ipv6_hdr(ra
)->saddr
))
1155 goto nla_put_failure
;
1156 nlmsg_end(skb
, nlh
);
1158 rtnl_notify(skb
, net
, 0, RTNLGRP_ND_USEROPT
, NULL
, GFP_ATOMIC
);
1165 rtnl_set_sk_err(net
, RTNLGRP_ND_USEROPT
, err
);
1168 static void ndisc_router_discovery(struct sk_buff
*skb
)
1170 struct ra_msg
*ra_msg
= (struct ra_msg
*)skb_transport_header(skb
);
1171 struct neighbour
*neigh
= NULL
;
1172 struct inet6_dev
*in6_dev
;
1173 struct fib6_info
*rt
= NULL
;
1176 struct ndisc_options ndopts
;
1178 unsigned int pref
= 0;
1180 bool send_ifinfo_notify
= false;
1182 __u8
*opt
= (__u8
*)(ra_msg
+ 1);
1184 optlen
= (skb_tail_pointer(skb
) - skb_transport_header(skb
)) -
1185 sizeof(struct ra_msg
);
1188 "RA: %s, dev: %s\n",
1189 __func__
, skb
->dev
->name
);
1190 if (!(ipv6_addr_type(&ipv6_hdr(skb
)->saddr
) & IPV6_ADDR_LINKLOCAL
)) {
1191 ND_PRINTK(2, warn
, "RA: source address is not link-local\n");
1195 ND_PRINTK(2, warn
, "RA: packet too short\n");
1199 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1200 if (skb
->ndisc_nodetype
== NDISC_NODETYPE_HOST
) {
1201 ND_PRINTK(2, warn
, "RA: from host or unauthorized router\n");
1207 * set the RA_RECV flag in the interface
1210 in6_dev
= __in6_dev_get(skb
->dev
);
1212 ND_PRINTK(0, err
, "RA: can't find inet6 device for %s\n",
1217 if (!ndisc_parse_options(skb
->dev
, opt
, optlen
, &ndopts
)) {
1218 ND_PRINTK(2, warn
, "RA: invalid ND options\n");
1222 if (!ipv6_accept_ra(in6_dev
)) {
1224 "RA: %s, did not accept ra for dev: %s\n",
1225 __func__
, skb
->dev
->name
);
1226 goto skip_linkparms
;
1229 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1230 /* skip link-specific parameters from interior routers */
1231 if (skb
->ndisc_nodetype
== NDISC_NODETYPE_NODEFAULT
) {
1233 "RA: %s, nodetype is NODEFAULT, dev: %s\n",
1234 __func__
, skb
->dev
->name
);
1235 goto skip_linkparms
;
1239 if (in6_dev
->if_flags
& IF_RS_SENT
) {
1241 * flag that an RA was received after an RS was sent
1242 * out on this interface.
1244 in6_dev
->if_flags
|= IF_RA_RCVD
;
1248 * Remember the managed/otherconf flags from most recently
1249 * received RA message (RFC 2462) -- yoshfuji
1251 old_if_flags
= in6_dev
->if_flags
;
1252 in6_dev
->if_flags
= (in6_dev
->if_flags
& ~(IF_RA_MANAGED
|
1254 (ra_msg
->icmph
.icmp6_addrconf_managed
?
1255 IF_RA_MANAGED
: 0) |
1256 (ra_msg
->icmph
.icmp6_addrconf_other
?
1257 IF_RA_OTHERCONF
: 0);
1259 if (old_if_flags
!= in6_dev
->if_flags
)
1260 send_ifinfo_notify
= true;
1262 if (!in6_dev
->cnf
.accept_ra_defrtr
) {
1264 "RA: %s, defrtr is false for dev: %s\n",
1265 __func__
, skb
->dev
->name
);
1269 /* Do not accept RA with source-addr found on local machine unless
1270 * accept_ra_from_local is set to true.
1272 net
= dev_net(in6_dev
->dev
);
1273 if (!in6_dev
->cnf
.accept_ra_from_local
&&
1274 ipv6_chk_addr(net
, &ipv6_hdr(skb
)->saddr
, in6_dev
->dev
, 0)) {
1276 "RA from local address detected on dev: %s: default router ignored\n",
1281 lifetime
= ntohs(ra_msg
->icmph
.icmp6_rt_lifetime
);
1283 #ifdef CONFIG_IPV6_ROUTER_PREF
1284 pref
= ra_msg
->icmph
.icmp6_router_pref
;
1285 /* 10b is handled as if it were 00b (medium) */
1286 if (pref
== ICMPV6_ROUTER_PREF_INVALID
||
1287 !in6_dev
->cnf
.accept_ra_rtr_pref
)
1288 pref
= ICMPV6_ROUTER_PREF_MEDIUM
;
1290 /* routes added from RAs do not use nexthop objects */
1291 rt
= rt6_get_dflt_router(net
, &ipv6_hdr(skb
)->saddr
, skb
->dev
);
1293 neigh
= ip6_neigh_lookup(&rt
->fib6_nh
->fib_nh_gw6
,
1294 rt
->fib6_nh
->fib_nh_dev
, NULL
,
1295 &ipv6_hdr(skb
)->saddr
);
1298 "RA: %s got default router without neighbour\n",
1300 fib6_info_release(rt
);
1304 if (rt
&& lifetime
== 0) {
1305 ip6_del_rt(net
, rt
, false);
1309 ND_PRINTK(3, info
, "RA: rt: %p lifetime: %d, for dev: %s\n",
1310 rt
, lifetime
, skb
->dev
->name
);
1311 if (!rt
&& lifetime
) {
1312 ND_PRINTK(3, info
, "RA: adding default router\n");
1314 rt
= rt6_add_dflt_router(net
, &ipv6_hdr(skb
)->saddr
,
1318 "RA: %s failed to add default route\n",
1323 neigh
= ip6_neigh_lookup(&rt
->fib6_nh
->fib_nh_gw6
,
1324 rt
->fib6_nh
->fib_nh_dev
, NULL
,
1325 &ipv6_hdr(skb
)->saddr
);
1328 "RA: %s got default router without neighbour\n",
1330 fib6_info_release(rt
);
1333 neigh
->flags
|= NTF_ROUTER
;
1335 rt
->fib6_flags
= (rt
->fib6_flags
& ~RTF_PREF_MASK
) | RTF_PREF(pref
);
1339 fib6_set_expires(rt
, jiffies
+ (HZ
* lifetime
));
1340 if (in6_dev
->cnf
.accept_ra_min_hop_limit
< 256 &&
1341 ra_msg
->icmph
.icmp6_hop_limit
) {
1342 if (in6_dev
->cnf
.accept_ra_min_hop_limit
<= ra_msg
->icmph
.icmp6_hop_limit
) {
1343 in6_dev
->cnf
.hop_limit
= ra_msg
->icmph
.icmp6_hop_limit
;
1344 fib6_metric_set(rt
, RTAX_HOPLIMIT
,
1345 ra_msg
->icmph
.icmp6_hop_limit
);
1347 ND_PRINTK(2, warn
, "RA: Got route advertisement with lower hop_limit than minimum\n");
1354 * Update Reachable Time and Retrans Timer
1357 if (in6_dev
->nd_parms
) {
1358 unsigned long rtime
= ntohl(ra_msg
->retrans_timer
);
1360 if (rtime
&& rtime
/1000 < MAX_SCHEDULE_TIMEOUT
/HZ
) {
1361 rtime
= (rtime
*HZ
)/1000;
1364 NEIGH_VAR_SET(in6_dev
->nd_parms
, RETRANS_TIME
, rtime
);
1365 in6_dev
->tstamp
= jiffies
;
1366 send_ifinfo_notify
= true;
1369 rtime
= ntohl(ra_msg
->reachable_time
);
1370 if (rtime
&& rtime
/1000 < MAX_SCHEDULE_TIMEOUT
/(3*HZ
)) {
1371 rtime
= (rtime
*HZ
)/1000;
1376 if (rtime
!= NEIGH_VAR(in6_dev
->nd_parms
, BASE_REACHABLE_TIME
)) {
1377 NEIGH_VAR_SET(in6_dev
->nd_parms
,
1378 BASE_REACHABLE_TIME
, rtime
);
1379 NEIGH_VAR_SET(in6_dev
->nd_parms
,
1380 GC_STALETIME
, 3 * rtime
);
1381 in6_dev
->nd_parms
->reachable_time
= neigh_rand_reach_time(rtime
);
1382 in6_dev
->tstamp
= jiffies
;
1383 send_ifinfo_notify
= true;
1389 * Send a notify if RA changed managed/otherconf flags or timer settings
1391 if (send_ifinfo_notify
)
1392 inet6_ifinfo_notify(RTM_NEWLINK
, in6_dev
);
1401 neigh
= __neigh_lookup(&nd_tbl
, &ipv6_hdr(skb
)->saddr
,
1405 if (ndopts
.nd_opts_src_lladdr
) {
1406 lladdr
= ndisc_opt_addr_data(ndopts
.nd_opts_src_lladdr
,
1410 "RA: invalid link-layer address length\n");
1414 ndisc_update(skb
->dev
, neigh
, lladdr
, NUD_STALE
,
1415 NEIGH_UPDATE_F_WEAK_OVERRIDE
|
1416 NEIGH_UPDATE_F_OVERRIDE
|
1417 NEIGH_UPDATE_F_OVERRIDE_ISROUTER
|
1418 NEIGH_UPDATE_F_ISROUTER
,
1419 NDISC_ROUTER_ADVERTISEMENT
, &ndopts
);
1422 if (!ipv6_accept_ra(in6_dev
)) {
1424 "RA: %s, accept_ra is false for dev: %s\n",
1425 __func__
, skb
->dev
->name
);
1429 #ifdef CONFIG_IPV6_ROUTE_INFO
1430 if (!in6_dev
->cnf
.accept_ra_from_local
&&
1431 ipv6_chk_addr(dev_net(in6_dev
->dev
), &ipv6_hdr(skb
)->saddr
,
1434 "RA from local address detected on dev: %s: router info ignored.\n",
1436 goto skip_routeinfo
;
1439 if (in6_dev
->cnf
.accept_ra_rtr_pref
&& ndopts
.nd_opts_ri
) {
1440 struct nd_opt_hdr
*p
;
1441 for (p
= ndopts
.nd_opts_ri
;
1443 p
= ndisc_next_option(p
, ndopts
.nd_opts_ri_end
)) {
1444 struct route_info
*ri
= (struct route_info
*)p
;
1445 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1446 if (skb
->ndisc_nodetype
== NDISC_NODETYPE_NODEFAULT
&&
1447 ri
->prefix_len
== 0)
1450 if (ri
->prefix_len
== 0 &&
1451 !in6_dev
->cnf
.accept_ra_defrtr
)
1453 if (ri
->prefix_len
< in6_dev
->cnf
.accept_ra_rt_info_min_plen
)
1455 if (ri
->prefix_len
> in6_dev
->cnf
.accept_ra_rt_info_max_plen
)
1457 rt6_route_rcv(skb
->dev
, (u8
*)p
, (p
->nd_opt_len
) << 3,
1458 &ipv6_hdr(skb
)->saddr
);
1465 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1466 /* skip link-specific ndopts from interior routers */
1467 if (skb
->ndisc_nodetype
== NDISC_NODETYPE_NODEFAULT
) {
1469 "RA: %s, nodetype is NODEFAULT (interior routes), dev: %s\n",
1470 __func__
, skb
->dev
->name
);
1475 if (in6_dev
->cnf
.accept_ra_pinfo
&& ndopts
.nd_opts_pi
) {
1476 struct nd_opt_hdr
*p
;
1477 for (p
= ndopts
.nd_opts_pi
;
1479 p
= ndisc_next_option(p
, ndopts
.nd_opts_pi_end
)) {
1480 addrconf_prefix_rcv(skb
->dev
, (u8
*)p
,
1481 (p
->nd_opt_len
) << 3,
1482 ndopts
.nd_opts_src_lladdr
!= NULL
);
1486 if (ndopts
.nd_opts_mtu
&& in6_dev
->cnf
.accept_ra_mtu
) {
1490 memcpy(&n
, ((u8
*)(ndopts
.nd_opts_mtu
+1))+2, sizeof(mtu
));
1493 if (mtu
< IPV6_MIN_MTU
|| mtu
> skb
->dev
->mtu
) {
1494 ND_PRINTK(2, warn
, "RA: invalid mtu: %d\n", mtu
);
1495 } else if (in6_dev
->cnf
.mtu6
!= mtu
) {
1496 in6_dev
->cnf
.mtu6
= mtu
;
1497 fib6_metric_set(rt
, RTAX_MTU
, mtu
);
1498 rt6_mtu_change(skb
->dev
, mtu
);
1502 if (ndopts
.nd_useropts
) {
1503 struct nd_opt_hdr
*p
;
1504 for (p
= ndopts
.nd_useropts
;
1506 p
= ndisc_next_useropt(skb
->dev
, p
,
1507 ndopts
.nd_useropts_end
)) {
1508 ndisc_ra_useropt(skb
, p
);
1512 if (ndopts
.nd_opts_tgt_lladdr
|| ndopts
.nd_opts_rh
) {
1513 ND_PRINTK(2, warn
, "RA: invalid RA options\n");
1516 fib6_info_release(rt
);
1518 neigh_release(neigh
);
1521 static void ndisc_redirect_rcv(struct sk_buff
*skb
)
1524 struct ndisc_options ndopts
;
1525 struct rd_msg
*msg
= (struct rd_msg
*)skb_transport_header(skb
);
1526 u32 ndoptlen
= skb_tail_pointer(skb
) - (skb_transport_header(skb
) +
1527 offsetof(struct rd_msg
, opt
));
1529 #ifdef CONFIG_IPV6_NDISC_NODETYPE
1530 switch (skb
->ndisc_nodetype
) {
1531 case NDISC_NODETYPE_HOST
:
1532 case NDISC_NODETYPE_NODEFAULT
:
1534 "Redirect: from host or unauthorized router\n");
1539 if (!(ipv6_addr_type(&ipv6_hdr(skb
)->saddr
) & IPV6_ADDR_LINKLOCAL
)) {
1541 "Redirect: source address is not link-local\n");
1545 if (!ndisc_parse_options(skb
->dev
, msg
->opt
, ndoptlen
, &ndopts
))
1548 if (!ndopts
.nd_opts_rh
) {
1549 ip6_redirect_no_header(skb
, dev_net(skb
->dev
),
1554 hdr
= (u8
*)ndopts
.nd_opts_rh
;
1556 if (!pskb_pull(skb
, hdr
- skb_transport_header(skb
)))
1559 icmpv6_notify(skb
, NDISC_REDIRECT
, 0, 0);
1562 static void ndisc_fill_redirect_hdr_option(struct sk_buff
*skb
,
1563 struct sk_buff
*orig_skb
,
1566 u8
*opt
= skb_put(skb
, rd_len
);
1569 *(opt
++) = ND_OPT_REDIRECT_HDR
;
1570 *(opt
++) = (rd_len
>> 3);
1573 skb_copy_bits(orig_skb
, skb_network_offset(orig_skb
), opt
,
1577 void ndisc_send_redirect(struct sk_buff
*skb
, const struct in6_addr
*target
)
1579 struct net_device
*dev
= skb
->dev
;
1580 struct net
*net
= dev_net(dev
);
1581 struct sock
*sk
= net
->ipv6
.ndisc_sk
;
1583 struct inet_peer
*peer
;
1584 struct sk_buff
*buff
;
1586 struct in6_addr saddr_buf
;
1587 struct rt6_info
*rt
;
1588 struct dst_entry
*dst
;
1591 u8 ha_buf
[MAX_ADDR_LEN
], *ha
= NULL
,
1592 ops_data_buf
[NDISC_OPS_REDIRECT_DATA_SPACE
], *ops_data
= NULL
;
1595 if (netif_is_l3_master(skb
->dev
)) {
1596 dev
= __dev_get_by_index(dev_net(skb
->dev
), IPCB(skb
)->iif
);
1601 if (ipv6_get_lladdr(dev
, &saddr_buf
, IFA_F_TENTATIVE
)) {
1602 ND_PRINTK(2, warn
, "Redirect: no link-local address on %s\n",
1607 if (!ipv6_addr_equal(&ipv6_hdr(skb
)->daddr
, target
) &&
1608 ipv6_addr_type(target
) != (IPV6_ADDR_UNICAST
|IPV6_ADDR_LINKLOCAL
)) {
1610 "Redirect: target address is not link-local unicast\n");
1614 icmpv6_flow_init(sk
, &fl6
, NDISC_REDIRECT
,
1615 &saddr_buf
, &ipv6_hdr(skb
)->saddr
, dev
->ifindex
);
1617 dst
= ip6_route_output(net
, NULL
, &fl6
);
1622 dst
= xfrm_lookup(net
, dst
, flowi6_to_flowi(&fl6
), NULL
, 0);
1626 rt
= (struct rt6_info
*) dst
;
1628 if (rt
->rt6i_flags
& RTF_GATEWAY
) {
1630 "Redirect: destination is not a neighbour\n");
1633 peer
= inet_getpeer_v6(net
->ipv6
.peers
, &ipv6_hdr(skb
)->saddr
, 1);
1634 ret
= inet_peer_xrlim_allow(peer
, 1*HZ
);
1640 if (dev
->addr_len
) {
1641 struct neighbour
*neigh
= dst_neigh_lookup(skb_dst(skb
), target
);
1644 "Redirect: no neigh for target address\n");
1648 read_lock_bh(&neigh
->lock
);
1649 if (neigh
->nud_state
& NUD_VALID
) {
1650 memcpy(ha_buf
, neigh
->ha
, dev
->addr_len
);
1651 read_unlock_bh(&neigh
->lock
);
1653 optlen
+= ndisc_redirect_opt_addr_space(dev
, neigh
,
1657 read_unlock_bh(&neigh
->lock
);
1659 neigh_release(neigh
);
1662 rd_len
= min_t(unsigned int,
1663 IPV6_MIN_MTU
- sizeof(struct ipv6hdr
) - sizeof(*msg
) - optlen
,
1668 buff
= ndisc_alloc_skb(dev
, sizeof(*msg
) + optlen
);
1672 msg
= skb_put(buff
, sizeof(*msg
));
1673 *msg
= (struct rd_msg
) {
1675 .icmp6_type
= NDISC_REDIRECT
,
1678 .dest
= ipv6_hdr(skb
)->daddr
,
1682 * include target_address option
1686 ndisc_fill_redirect_addr_option(buff
, ha
, ops_data
);
1689 * build redirect option and copy skb over to the new packet.
1693 ndisc_fill_redirect_hdr_option(buff
, skb
, rd_len
);
1695 skb_dst_set(buff
, dst
);
1696 ndisc_send_skb(buff
, &ipv6_hdr(skb
)->saddr
, &saddr_buf
);
1703 static void pndisc_redo(struct sk_buff
*skb
)
1709 static bool ndisc_suppress_frag_ndisc(struct sk_buff
*skb
)
1711 struct inet6_dev
*idev
= __in6_dev_get(skb
->dev
);
1715 if (IP6CB(skb
)->flags
& IP6SKB_FRAGMENTED
&&
1716 idev
->cnf
.suppress_frag_ndisc
) {
1717 net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n");
1723 int ndisc_rcv(struct sk_buff
*skb
)
1727 if (ndisc_suppress_frag_ndisc(skb
))
1730 if (skb_linearize(skb
))
1733 msg
= (struct nd_msg
*)skb_transport_header(skb
);
1735 __skb_push(skb
, skb
->data
- skb_transport_header(skb
));
1737 if (ipv6_hdr(skb
)->hop_limit
!= 255) {
1738 ND_PRINTK(2, warn
, "NDISC: invalid hop-limit: %d\n",
1739 ipv6_hdr(skb
)->hop_limit
);
1743 if (msg
->icmph
.icmp6_code
!= 0) {
1744 ND_PRINTK(2, warn
, "NDISC: invalid ICMPv6 code: %d\n",
1745 msg
->icmph
.icmp6_code
);
1749 switch (msg
->icmph
.icmp6_type
) {
1750 case NDISC_NEIGHBOUR_SOLICITATION
:
1751 memset(NEIGH_CB(skb
), 0, sizeof(struct neighbour_cb
));
1755 case NDISC_NEIGHBOUR_ADVERTISEMENT
:
1759 case NDISC_ROUTER_SOLICITATION
:
1763 case NDISC_ROUTER_ADVERTISEMENT
:
1764 ndisc_router_discovery(skb
);
1767 case NDISC_REDIRECT
:
1768 ndisc_redirect_rcv(skb
);
1775 static int ndisc_netdev_event(struct notifier_block
*this, unsigned long event
, void *ptr
)
1777 struct net_device
*dev
= netdev_notifier_info_to_dev(ptr
);
1778 struct netdev_notifier_change_info
*change_info
;
1779 struct net
*net
= dev_net(dev
);
1780 struct inet6_dev
*idev
;
1783 case NETDEV_CHANGEADDR
:
1784 neigh_changeaddr(&nd_tbl
, dev
);
1785 fib6_run_gc(0, net
, false);
1788 idev
= in6_dev_get(dev
);
1791 if (idev
->cnf
.ndisc_notify
||
1792 net
->ipv6
.devconf_all
->ndisc_notify
)
1793 ndisc_send_unsol_na(dev
);
1798 if (change_info
->flags_changed
& IFF_NOARP
)
1799 neigh_changeaddr(&nd_tbl
, dev
);
1800 if (!netif_carrier_ok(dev
))
1801 neigh_carrier_down(&nd_tbl
, dev
);
1804 neigh_ifdown(&nd_tbl
, dev
);
1805 fib6_run_gc(0, net
, false);
1807 case NETDEV_NOTIFY_PEERS
:
1808 ndisc_send_unsol_na(dev
);
1817 static struct notifier_block ndisc_netdev_notifier
= {
1818 .notifier_call
= ndisc_netdev_event
,
1819 .priority
= ADDRCONF_NOTIFY_PRIORITY
- 5,
1822 #ifdef CONFIG_SYSCTL
1823 static void ndisc_warn_deprecated_sysctl(struct ctl_table
*ctl
,
1824 const char *func
, const char *dev_name
)
1826 static char warncomm
[TASK_COMM_LEN
];
1828 if (strcmp(warncomm
, current
->comm
) && warned
< 5) {
1829 strcpy(warncomm
, current
->comm
);
1830 pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n",
1832 dev_name
, ctl
->procname
,
1833 dev_name
, ctl
->procname
);
1838 int ndisc_ifinfo_sysctl_change(struct ctl_table
*ctl
, int write
, void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1840 struct net_device
*dev
= ctl
->extra1
;
1841 struct inet6_dev
*idev
;
1844 if ((strcmp(ctl
->procname
, "retrans_time") == 0) ||
1845 (strcmp(ctl
->procname
, "base_reachable_time") == 0))
1846 ndisc_warn_deprecated_sysctl(ctl
, "syscall", dev
? dev
->name
: "default");
1848 if (strcmp(ctl
->procname
, "retrans_time") == 0)
1849 ret
= neigh_proc_dointvec(ctl
, write
, buffer
, lenp
, ppos
);
1851 else if (strcmp(ctl
->procname
, "base_reachable_time") == 0)
1852 ret
= neigh_proc_dointvec_jiffies(ctl
, write
,
1853 buffer
, lenp
, ppos
);
1855 else if ((strcmp(ctl
->procname
, "retrans_time_ms") == 0) ||
1856 (strcmp(ctl
->procname
, "base_reachable_time_ms") == 0))
1857 ret
= neigh_proc_dointvec_ms_jiffies(ctl
, write
,
1858 buffer
, lenp
, ppos
);
1862 if (write
&& ret
== 0 && dev
&& (idev
= in6_dev_get(dev
)) != NULL
) {
1863 if (ctl
->data
== &NEIGH_VAR(idev
->nd_parms
, BASE_REACHABLE_TIME
))
1864 idev
->nd_parms
->reachable_time
=
1865 neigh_rand_reach_time(NEIGH_VAR(idev
->nd_parms
, BASE_REACHABLE_TIME
));
1866 idev
->tstamp
= jiffies
;
1867 inet6_ifinfo_notify(RTM_NEWLINK
, idev
);
1876 static int __net_init
ndisc_net_init(struct net
*net
)
1878 struct ipv6_pinfo
*np
;
1882 err
= inet_ctl_sock_create(&sk
, PF_INET6
,
1883 SOCK_RAW
, IPPROTO_ICMPV6
, net
);
1886 "NDISC: Failed to initialize the control socket (err %d)\n",
1891 net
->ipv6
.ndisc_sk
= sk
;
1894 np
->hop_limit
= 255;
1895 /* Do not loopback ndisc messages */
1901 static void __net_exit
ndisc_net_exit(struct net
*net
)
1903 inet_ctl_sock_destroy(net
->ipv6
.ndisc_sk
);
1906 static struct pernet_operations ndisc_net_ops
= {
1907 .init
= ndisc_net_init
,
1908 .exit
= ndisc_net_exit
,
1911 int __init
ndisc_init(void)
1915 err
= register_pernet_subsys(&ndisc_net_ops
);
1919 * Initialize the neighbour table
1921 neigh_table_init(NEIGH_ND_TABLE
, &nd_tbl
);
1923 #ifdef CONFIG_SYSCTL
1924 err
= neigh_sysctl_register(NULL
, &nd_tbl
.parms
,
1925 ndisc_ifinfo_sysctl_change
);
1927 goto out_unregister_pernet
;
1932 #ifdef CONFIG_SYSCTL
1933 out_unregister_pernet
:
1934 unregister_pernet_subsys(&ndisc_net_ops
);
1939 int __init
ndisc_late_init(void)
1941 return register_netdevice_notifier(&ndisc_netdev_notifier
);
1944 void ndisc_late_cleanup(void)
1946 unregister_netdevice_notifier(&ndisc_netdev_notifier
);
1949 void ndisc_cleanup(void)
1951 #ifdef CONFIG_SYSCTL
1952 neigh_sysctl_unregister(&nd_tbl
.parms
);
1954 neigh_table_clear(NEIGH_ND_TABLE
, &nd_tbl
);
1955 unregister_pernet_subsys(&ndisc_net_ops
);