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Commit | Line | Data |
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2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /* |
3 | * IPv6 input | |
1ab1457c | 4 | * Linux INET6 implementation |
1da177e4 LT |
5 | * |
6 | * Authors: | |
7 | * Pedro Roque <roque@di.fc.ul.pt> | |
8 | * Ian P. Morris <I.P.Morris@soton.ac.uk> | |
9 | * | |
1da177e4 | 10 | * Based in linux/net/ipv4/ip_input.c |
1da177e4 LT |
11 | */ |
12 | /* Changes | |
13 | * | |
67ba4152 IM |
14 | * Mitsuru KANDA @USAGI and |
15 | * YOSHIFUJI Hideaki @USAGI: Remove ipv6_parse_exthdrs(). | |
1da177e4 LT |
16 | */ |
17 | ||
18 | #include <linux/errno.h> | |
19 | #include <linux/types.h> | |
20 | #include <linux/socket.h> | |
21 | #include <linux/sockios.h> | |
1da177e4 LT |
22 | #include <linux/net.h> |
23 | #include <linux/netdevice.h> | |
24 | #include <linux/in6.h> | |
25 | #include <linux/icmpv6.h> | |
7bc570c8 | 26 | #include <linux/mroute6.h> |
5a0e3ad6 | 27 | #include <linux/slab.h> |
0e219ae4 | 28 | #include <linux/indirect_call_wrapper.h> |
1da177e4 LT |
29 | |
30 | #include <linux/netfilter.h> | |
31 | #include <linux/netfilter_ipv6.h> | |
32 | ||
33 | #include <net/sock.h> | |
34 | #include <net/snmp.h> | |
35 | ||
36 | #include <net/ipv6.h> | |
37 | #include <net/protocol.h> | |
38 | #include <net/transp_v6.h> | |
39 | #include <net/rawv6.h> | |
40 | #include <net/ndisc.h> | |
41 | #include <net/ip6_route.h> | |
42 | #include <net/addrconf.h> | |
43 | #include <net/xfrm.h> | |
1f07d03e | 44 | #include <net/inet_ecn.h> |
48fb6b55 | 45 | #include <net/dst_metadata.h> |
1da177e4 | 46 | |
97ff7ffb PA |
47 | INDIRECT_CALLABLE_DECLARE(void udp_v6_early_demux(struct sk_buff *)); |
48 | INDIRECT_CALLABLE_DECLARE(void tcp_v6_early_demux(struct sk_buff *)); | |
d8269e2c EC |
49 | static void ip6_rcv_finish_core(struct net *net, struct sock *sk, |
50 | struct sk_buff *skb) | |
1da177e4 | 51 | { |
dddb64bc | 52 | void (*edemux)(struct sk_buff *skb); |
53 | ||
e21145a9 | 54 | if (net->ipv4.sysctl_ip_early_demux && !skb_dst(skb) && skb->sk == NULL) { |
c7109986 ED |
55 | const struct inet6_protocol *ipprot; |
56 | ||
c7109986 | 57 | ipprot = rcu_dereference(inet6_protos[ipv6_hdr(skb)->nexthdr]); |
dddb64bc | 58 | if (ipprot && (edemux = READ_ONCE(ipprot->early_demux))) |
97ff7ffb PA |
59 | INDIRECT_CALL_2(edemux, tcp_v6_early_demux, |
60 | udp_v6_early_demux, skb); | |
c7109986 | 61 | } |
48fb6b55 | 62 | if (!skb_valid_dst(skb)) |
1da177e4 | 63 | ip6_route_input(skb); |
d8269e2c EC |
64 | } |
65 | ||
66 | int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb) | |
67 | { | |
68 | /* if ingress device is enslaved to an L3 master device pass the | |
69 | * skb to its handler for processing | |
70 | */ | |
71 | skb = l3mdev_ip6_rcv(skb); | |
72 | if (!skb) | |
73 | return NET_RX_SUCCESS; | |
74 | ip6_rcv_finish_core(net, sk, skb); | |
1da177e4 LT |
75 | |
76 | return dst_input(skb); | |
77 | } | |
78 | ||
d8269e2c EC |
79 | static void ip6_sublist_rcv_finish(struct list_head *head) |
80 | { | |
81 | struct sk_buff *skb, *next; | |
82 | ||
83 | list_for_each_entry_safe(skb, next, head, list) | |
84 | dst_input(skb); | |
85 | } | |
86 | ||
87 | static void ip6_list_rcv_finish(struct net *net, struct sock *sk, | |
88 | struct list_head *head) | |
89 | { | |
90 | struct dst_entry *curr_dst = NULL; | |
91 | struct sk_buff *skb, *next; | |
92 | struct list_head sublist; | |
93 | ||
94 | INIT_LIST_HEAD(&sublist); | |
95 | list_for_each_entry_safe(skb, next, head, list) { | |
96 | struct dst_entry *dst; | |
97 | ||
22f6bbb7 | 98 | skb_list_del_init(skb); |
d8269e2c EC |
99 | /* if ingress device is enslaved to an L3 master device pass the |
100 | * skb to its handler for processing | |
101 | */ | |
102 | skb = l3mdev_ip6_rcv(skb); | |
103 | if (!skb) | |
104 | continue; | |
105 | ip6_rcv_finish_core(net, sk, skb); | |
106 | dst = skb_dst(skb); | |
107 | if (curr_dst != dst) { | |
108 | /* dispatch old sublist */ | |
109 | if (!list_empty(&sublist)) | |
110 | ip6_sublist_rcv_finish(&sublist); | |
111 | /* start new sublist */ | |
112 | INIT_LIST_HEAD(&sublist); | |
113 | curr_dst = dst; | |
114 | } | |
115 | list_add_tail(&skb->list, &sublist); | |
116 | } | |
117 | /* dispatch final sublist */ | |
118 | ip6_sublist_rcv_finish(&sublist); | |
119 | } | |
120 | ||
121 | static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev, | |
122 | struct net *net) | |
1da177e4 | 123 | { |
b71d1d42 | 124 | const struct ipv6hdr *hdr; |
67ba4152 | 125 | u32 pkt_len; |
a11d206d | 126 | struct inet6_dev *idev; |
1da177e4 | 127 | |
a11d206d YH |
128 | if (skb->pkt_type == PACKET_OTHERHOST) { |
129 | kfree_skb(skb); | |
d8269e2c | 130 | return NULL; |
a11d206d YH |
131 | } |
132 | ||
133 | rcu_read_lock(); | |
1da177e4 | 134 | |
a11d206d YH |
135 | idev = __in6_dev_get(skb->dev); |
136 | ||
c2005eb0 | 137 | __IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_IN, skb->len); |
1da177e4 | 138 | |
778d80be YH |
139 | if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL || |
140 | !idev || unlikely(idev->cnf.disable_ipv6)) { | |
1d015503 | 141 | __IP6_INC_STATS(net, idev, IPSTATS_MIB_INDISCARDS); |
71f6f6df | 142 | goto drop; |
1da177e4 LT |
143 | } |
144 | ||
6b7fdc3a GC |
145 | memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); |
146 | ||
1da177e4 LT |
147 | /* |
148 | * Store incoming device index. When the packet will | |
149 | * be queued, we cannot refer to skb->dev anymore. | |
150 | * | |
151 | * BTW, when we send a packet for our own local address on a | |
152 | * non-loopback interface (e.g. ethX), it is being delivered | |
de3cb747 | 153 | * via the loopback interface (lo) here; skb->dev = loopback_dev. |
1da177e4 LT |
154 | * It, however, should be considered as if it is being |
155 | * arrived via the sending interface (ethX), because of the | |
156 | * nature of scoping architecture. --yoshfuji | |
157 | */ | |
48fb6b55 | 158 | IP6CB(skb)->iif = skb_valid_dst(skb) ? ip6_dst_idev(skb_dst(skb))->dev->ifindex : dev->ifindex; |
1da177e4 | 159 | |
2889139a | 160 | if (unlikely(!pskb_may_pull(skb, sizeof(*hdr)))) |
1da177e4 LT |
161 | goto err; |
162 | ||
0660e03f | 163 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
164 | |
165 | if (hdr->version != 6) | |
166 | goto err; | |
167 | ||
1d015503 ED |
168 | __IP6_ADD_STATS(net, idev, |
169 | IPSTATS_MIB_NOECTPKTS + | |
1f07d03e | 170 | (ipv6_get_dsfield(hdr) & INET_ECN_MASK), |
1d015503 | 171 | max_t(unsigned short, 1, skb_shinfo(skb)->gso_segs)); |
f630e43a YH |
172 | /* |
173 | * RFC4291 2.5.3 | |
0aa8c13e FW |
174 | * The loopback address must not be used as the source address in IPv6 |
175 | * packets that are sent outside of a single node. [..] | |
f630e43a YH |
176 | * A packet received on an interface with a destination address |
177 | * of loopback must be dropped. | |
178 | */ | |
0aa8c13e FW |
179 | if ((ipv6_addr_loopback(&hdr->saddr) || |
180 | ipv6_addr_loopback(&hdr->daddr)) && | |
3ede0bbc RS |
181 | !(dev->flags & IFF_LOOPBACK) && |
182 | !netif_is_l3_master(dev)) | |
f630e43a YH |
183 | goto err; |
184 | ||
1c4a154e HFS |
185 | /* RFC4291 Errata ID: 3480 |
186 | * Interface-Local scope spans only a single interface on a | |
187 | * node and is useful only for loopback transmission of | |
188 | * multicast. Packets with interface-local scope received | |
189 | * from another node must be discarded. | |
190 | */ | |
191 | if (!(skb->pkt_type == PACKET_LOOPBACK || | |
192 | dev->flags & IFF_LOOPBACK) && | |
193 | ipv6_addr_is_multicast(&hdr->daddr) && | |
194 | IPV6_ADDR_MC_SCOPE(&hdr->daddr) == 1) | |
195 | goto err; | |
196 | ||
abbc3043 JB |
197 | /* If enabled, drop unicast packets that were encapsulated in link-layer |
198 | * multicast or broadcast to protected against the so-called "hole-196" | |
199 | * attack in 802.11 wireless. | |
200 | */ | |
201 | if (!ipv6_addr_is_multicast(&hdr->daddr) && | |
202 | (skb->pkt_type == PACKET_BROADCAST || | |
203 | skb->pkt_type == PACKET_MULTICAST) && | |
204 | idev->cnf.drop_unicast_in_l2_multicast) | |
205 | goto err; | |
206 | ||
20314092 HFS |
207 | /* RFC4291 2.7 |
208 | * Nodes must not originate a packet to a multicast address whose scope | |
209 | * field contains the reserved value 0; if such a packet is received, it | |
210 | * must be silently dropped. | |
211 | */ | |
212 | if (ipv6_addr_is_multicast(&hdr->daddr) && | |
213 | IPV6_ADDR_MC_SCOPE(&hdr->daddr) == 0) | |
214 | goto err; | |
215 | ||
c457338d BH |
216 | /* |
217 | * RFC4291 2.7 | |
218 | * Multicast addresses must not be used as source addresses in IPv6 | |
219 | * packets or appear in any Routing header. | |
220 | */ | |
221 | if (ipv6_addr_is_multicast(&hdr->saddr)) | |
222 | goto err; | |
223 | ||
b0e380b1 | 224 | skb->transport_header = skb->network_header + sizeof(*hdr); |
951dbc8a PM |
225 | IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); |
226 | ||
1da177e4 LT |
227 | pkt_len = ntohs(hdr->payload_len); |
228 | ||
229 | /* pkt_len may be zero if Jumbo payload option is present */ | |
230 | if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) { | |
60e5c166 | 231 | if (pkt_len + sizeof(struct ipv6hdr) > skb->len) { |
1d015503 ED |
232 | __IP6_INC_STATS(net, |
233 | idev, IPSTATS_MIB_INTRUNCATEDPKTS); | |
60e5c166 MC |
234 | goto drop; |
235 | } | |
1da177e4 | 236 | if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) { |
1d015503 | 237 | __IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
238 | goto drop; |
239 | } | |
0660e03f | 240 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
241 | } |
242 | ||
243 | if (hdr->nexthdr == NEXTHDR_HOP) { | |
e5bbef20 | 244 | if (ipv6_parse_hopopts(skb) < 0) { |
1d015503 | 245 | __IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); |
a11d206d | 246 | rcu_read_unlock(); |
d8269e2c | 247 | return NULL; |
1da177e4 | 248 | } |
1da177e4 LT |
249 | } |
250 | ||
a11d206d YH |
251 | rcu_read_unlock(); |
252 | ||
71f9dacd HX |
253 | /* Must drop socket now because of tproxy. */ |
254 | skb_orphan(skb); | |
255 | ||
d8269e2c | 256 | return skb; |
1da177e4 | 257 | err: |
1d015503 | 258 | __IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); |
1da177e4 | 259 | drop: |
a11d206d | 260 | rcu_read_unlock(); |
1da177e4 | 261 | kfree_skb(skb); |
d8269e2c EC |
262 | return NULL; |
263 | } | |
264 | ||
265 | int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) | |
266 | { | |
267 | struct net *net = dev_net(skb->dev); | |
268 | ||
269 | skb = ip6_rcv_core(skb, dev, net); | |
270 | if (skb == NULL) | |
271 | return NET_RX_DROP; | |
272 | return NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, | |
273 | net, NULL, skb, dev, NULL, | |
274 | ip6_rcv_finish); | |
275 | } | |
276 | ||
277 | static void ip6_sublist_rcv(struct list_head *head, struct net_device *dev, | |
278 | struct net *net) | |
279 | { | |
280 | NF_HOOK_LIST(NFPROTO_IPV6, NF_INET_PRE_ROUTING, net, NULL, | |
281 | head, dev, NULL, ip6_rcv_finish); | |
282 | ip6_list_rcv_finish(net, NULL, head); | |
283 | } | |
284 | ||
285 | /* Receive a list of IPv6 packets */ | |
286 | void ipv6_list_rcv(struct list_head *head, struct packet_type *pt, | |
287 | struct net_device *orig_dev) | |
288 | { | |
289 | struct net_device *curr_dev = NULL; | |
290 | struct net *curr_net = NULL; | |
291 | struct sk_buff *skb, *next; | |
292 | struct list_head sublist; | |
293 | ||
294 | INIT_LIST_HEAD(&sublist); | |
295 | list_for_each_entry_safe(skb, next, head, list) { | |
296 | struct net_device *dev = skb->dev; | |
297 | struct net *net = dev_net(dev); | |
298 | ||
22f6bbb7 | 299 | skb_list_del_init(skb); |
d8269e2c EC |
300 | skb = ip6_rcv_core(skb, dev, net); |
301 | if (skb == NULL) | |
302 | continue; | |
303 | ||
304 | if (curr_dev != dev || curr_net != net) { | |
305 | /* dispatch old sublist */ | |
306 | if (!list_empty(&sublist)) | |
307 | ip6_sublist_rcv(&sublist, curr_dev, curr_net); | |
308 | /* start new sublist */ | |
309 | INIT_LIST_HEAD(&sublist); | |
310 | curr_dev = dev; | |
311 | curr_net = net; | |
312 | } | |
313 | list_add_tail(&skb->list, &sublist); | |
314 | } | |
315 | /* dispatch final sublist */ | |
316 | ip6_sublist_rcv(&sublist, curr_dev, curr_net); | |
1da177e4 LT |
317 | } |
318 | ||
0e219ae4 PA |
319 | INDIRECT_CALLABLE_DECLARE(int udpv6_rcv(struct sk_buff *)); |
320 | INDIRECT_CALLABLE_DECLARE(int tcp_v6_rcv(struct sk_buff *)); | |
321 | ||
1da177e4 LT |
322 | /* |
323 | * Deliver the packet to the host | |
324 | */ | |
80bde363 PA |
325 | void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr, |
326 | bool have_final) | |
1da177e4 | 327 | { |
41135cc8 | 328 | const struct inet6_protocol *ipprot; |
f9242b6b | 329 | struct inet6_dev *idev; |
1da177e4 | 330 | unsigned int nhoff; |
a50feda5 | 331 | bool raw; |
1da177e4 | 332 | |
1da177e4 LT |
333 | /* |
334 | * Parse extension headers | |
335 | */ | |
336 | ||
1b0ccfe5 | 337 | resubmit: |
adf30907 | 338 | idev = ip6_dst_idev(skb_dst(skb)); |
951dbc8a | 339 | nhoff = IP6CB(skb)->nhoff; |
80bde363 PA |
340 | if (!have_final) { |
341 | if (!pskb_pull(skb, skb_transport_offset(skb))) | |
342 | goto discard; | |
343 | nexthdr = skb_network_header(skb)[nhoff]; | |
344 | } | |
1da177e4 | 345 | |
4c64242a | 346 | resubmit_final: |
69d6da0b | 347 | raw = raw6_local_deliver(skb, nexthdr); |
e5d08d71 | 348 | ipprot = rcu_dereference(inet6_protos[nexthdr]); |
53b24b8f | 349 | if (ipprot) { |
1da177e4 | 350 | int ret; |
1ab1457c | 351 | |
1da44f9c TH |
352 | if (have_final) { |
353 | if (!(ipprot->flags & INET6_PROTO_FINAL)) { | |
354 | /* Once we've seen a final protocol don't | |
355 | * allow encapsulation on any non-final | |
356 | * ones. This allows foo in UDP encapsulation | |
357 | * to work. | |
358 | */ | |
359 | goto discard; | |
360 | } | |
361 | } else if (ipprot->flags & INET6_PROTO_FINAL) { | |
b71d1d42 | 362 | const struct ipv6hdr *hdr; |
5226b6a9 MM |
363 | int sdif = inet6_sdif(skb); |
364 | struct net_device *dev; | |
1da177e4 | 365 | |
1da44f9c TH |
366 | /* Only do this once for first final protocol */ |
367 | have_final = true; | |
368 | ||
9fb9cbb1 YK |
369 | /* Free reference early: we don't need it any more, |
370 | and it may hold ip_conntrack module loaded | |
371 | indefinitely. */ | |
372 | nf_reset(skb); | |
373 | ||
d56f90a7 | 374 | skb_postpull_rcsum(skb, skb_network_header(skb), |
cfe1fc77 | 375 | skb_network_header_len(skb)); |
0660e03f | 376 | hdr = ipv6_hdr(skb); |
5226b6a9 MM |
377 | |
378 | /* skb->dev passed may be master dev for vrfs. */ | |
379 | if (sdif) { | |
380 | dev = dev_get_by_index_rcu(net, sdif); | |
381 | if (!dev) | |
382 | goto discard; | |
383 | } else { | |
384 | dev = skb->dev; | |
385 | } | |
386 | ||
1da177e4 | 387 | if (ipv6_addr_is_multicast(&hdr->daddr) && |
5226b6a9 MM |
388 | !ipv6_chk_mcast_addr(dev, &hdr->daddr, |
389 | &hdr->saddr) && | |
daad1512 | 390 | !ipv6_is_mld(skb, nexthdr, skb_network_header_len(skb))) |
1da177e4 LT |
391 | goto discard; |
392 | } | |
393 | if (!(ipprot->flags & INET6_PROTO_NOPOLICY) && | |
1ab1457c | 394 | !xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) |
1da177e4 | 395 | goto discard; |
1ab1457c | 396 | |
0e219ae4 PA |
397 | ret = INDIRECT_CALL_2(ipprot->handler, tcp_v6_rcv, udpv6_rcv, |
398 | skb); | |
4c64242a TH |
399 | if (ret > 0) { |
400 | if (ipprot->flags & INET6_PROTO_FINAL) { | |
401 | /* Not an extension header, most likely UDP | |
402 | * encapsulation. Use return value as nexthdr | |
403 | * protocol not nhoff (which presumably is | |
404 | * not set by handler). | |
405 | */ | |
406 | nexthdr = ret; | |
407 | goto resubmit_final; | |
408 | } else { | |
409 | goto resubmit; | |
410 | } | |
411 | } else if (ret == 0) { | |
1d015503 | 412 | __IP6_INC_STATS(net, idev, IPSTATS_MIB_INDELIVERS); |
4c64242a | 413 | } |
1da177e4 | 414 | } else { |
69d6da0b | 415 | if (!raw) { |
1da177e4 | 416 | if (xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
1d015503 ED |
417 | __IP6_INC_STATS(net, idev, |
418 | IPSTATS_MIB_INUNKNOWNPROTOS); | |
fad87aca | 419 | icmpv6_send(skb, ICMPV6_PARAMPROB, |
3ffe533c | 420 | ICMPV6_UNK_NEXTHDR, nhoff); |
1da177e4 | 421 | } |
d8c6f4b9 NH |
422 | kfree_skb(skb); |
423 | } else { | |
1d015503 | 424 | __IP6_INC_STATS(net, idev, IPSTATS_MIB_INDELIVERS); |
d8c6f4b9 NH |
425 | consume_skb(skb); |
426 | } | |
1da177e4 | 427 | } |
80bde363 | 428 | return; |
1da177e4 LT |
429 | |
430 | discard: | |
1d015503 | 431 | __IP6_INC_STATS(net, idev, IPSTATS_MIB_INDISCARDS); |
1da177e4 | 432 | kfree_skb(skb); |
80bde363 PA |
433 | } |
434 | ||
435 | static int ip6_input_finish(struct net *net, struct sock *sk, struct sk_buff *skb) | |
436 | { | |
437 | rcu_read_lock(); | |
438 | ip6_protocol_deliver_rcu(net, skb, 0, false); | |
439 | rcu_read_unlock(); | |
440 | ||
1da177e4 LT |
441 | return 0; |
442 | } | |
443 | ||
444 | ||
445 | int ip6_input(struct sk_buff *skb) | |
446 | { | |
29a26a56 EB |
447 | return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_IN, |
448 | dev_net(skb->dev), NULL, skb, skb->dev, NULL, | |
6e23ae2a | 449 | ip6_input_finish); |
1da177e4 | 450 | } |
b4869aa2 | 451 | EXPORT_SYMBOL_GPL(ip6_input); |
1da177e4 LT |
452 | |
453 | int ip6_mc_input(struct sk_buff *skb) | |
454 | { | |
5226b6a9 | 455 | int sdif = inet6_sdif(skb); |
b71d1d42 | 456 | const struct ipv6hdr *hdr; |
5226b6a9 | 457 | struct net_device *dev; |
a50feda5 | 458 | bool deliver; |
1da177e4 | 459 | |
c2005eb0 | 460 | __IP6_UPD_PO_STATS(dev_net(skb_dst(skb)->dev), |
bdb7cc64 | 461 | __in6_dev_get_safely(skb->dev), IPSTATS_MIB_INMCAST, |
edf391ff | 462 | skb->len); |
1da177e4 | 463 | |
5226b6a9 MM |
464 | /* skb->dev passed may be master dev for vrfs. */ |
465 | if (sdif) { | |
466 | rcu_read_lock(); | |
467 | dev = dev_get_by_index_rcu(dev_net(skb->dev), sdif); | |
468 | if (!dev) { | |
469 | rcu_read_unlock(); | |
470 | kfree_skb(skb); | |
471 | return -ENODEV; | |
472 | } | |
473 | } else { | |
474 | dev = skb->dev; | |
475 | } | |
476 | ||
0660e03f | 477 | hdr = ipv6_hdr(skb); |
5226b6a9 MM |
478 | deliver = ipv6_chk_mcast_addr(dev, &hdr->daddr, NULL); |
479 | if (sdif) | |
480 | rcu_read_unlock(); | |
1da177e4 | 481 | |
7bc570c8 | 482 | #ifdef CONFIG_IPV6_MROUTE |
1da177e4 | 483 | /* |
7bc570c8 | 484 | * IPv6 multicast router mode is now supported ;) |
1da177e4 | 485 | */ |
53b7997f | 486 | if (dev_net(skb->dev)->ipv6.devconf_all->mc_forwarding && |
ddf64354 HFS |
487 | !(ipv6_addr_type(&hdr->daddr) & |
488 | (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)) && | |
7bc570c8 YH |
489 | likely(!(IP6CB(skb)->flags & IP6SKB_FORWARDED))) { |
490 | /* | |
491 | * Okay, we try to forward - split and duplicate | |
492 | * packets. | |
493 | */ | |
494 | struct sk_buff *skb2; | |
495 | struct inet6_skb_parm *opt = IP6CB(skb); | |
496 | ||
497 | /* Check for MLD */ | |
dd3332bf | 498 | if (unlikely(opt->flags & IP6SKB_ROUTERALERT)) { |
7bc570c8 | 499 | /* Check if this is a mld message */ |
7bc570c8 | 500 | u8 nexthdr = hdr->nexthdr; |
75f2811c | 501 | __be16 frag_off; |
7bc570c8 YH |
502 | int offset; |
503 | ||
504 | /* Check if the value of Router Alert | |
505 | * is for MLD (0x0000). | |
506 | */ | |
dd3332bf | 507 | if (opt->ra == htons(IPV6_OPT_ROUTERALERT_MLD)) { |
a50feda5 | 508 | deliver = false; |
aba6096b | 509 | |
7bc570c8 YH |
510 | if (!ipv6_ext_hdr(nexthdr)) { |
511 | /* BUG */ | |
aba6096b | 512 | goto out; |
7bc570c8 YH |
513 | } |
514 | offset = ipv6_skip_exthdr(skb, sizeof(*hdr), | |
75f2811c | 515 | &nexthdr, &frag_off); |
7bc570c8 | 516 | if (offset < 0) |
aba6096b | 517 | goto out; |
7bc570c8 | 518 | |
4c938d22 A |
519 | if (ipv6_is_mld(skb, nexthdr, offset)) |
520 | deliver = true; | |
7bc570c8 | 521 | |
4c938d22 | 522 | goto out; |
7bc570c8 YH |
523 | } |
524 | /* unknown RA - process it normally */ | |
525 | } | |
1da177e4 | 526 | |
7bc570c8 YH |
527 | if (deliver) |
528 | skb2 = skb_clone(skb, GFP_ATOMIC); | |
529 | else { | |
530 | skb2 = skb; | |
531 | skb = NULL; | |
532 | } | |
1ab1457c | 533 | |
7bc570c8 | 534 | if (skb2) { |
7bc570c8 | 535 | ip6_mr_input(skb2); |
1da177e4 LT |
536 | } |
537 | } | |
7bc570c8 | 538 | out: |
aba6096b YH |
539 | #endif |
540 | if (likely(deliver)) | |
1da177e4 | 541 | ip6_input(skb); |
aba6096b YH |
542 | else { |
543 | /* discard */ | |
544 | kfree_skb(skb); | |
1da177e4 | 545 | } |
1da177e4 LT |
546 | |
547 | return 0; | |
548 | } |