blob: 1ca5d45a12e8973408ececb5ebd4e1daa3e391f9 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * IPv6 input
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +09003 * Linux INET6 implementation
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Ian P. Morris <I.P.Morris@soton.ac.uk>
8 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 * Based in linux/net/ipv4/ip_input.c
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
15 */
16/* Changes
17 *
18 * Mitsuru KANDA @USAGI and
19 * YOSHIFUJI Hideaki @USAGI: Remove ipv6_parse_exthdrs().
20 */
21
22#include <linux/errno.h>
23#include <linux/types.h>
24#include <linux/socket.h>
25#include <linux/sockios.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/net.h>
27#include <linux/netdevice.h>
28#include <linux/in6.h>
29#include <linux/icmpv6.h>
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +090030#include <linux/mroute6.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090031#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032
33#include <linux/netfilter.h>
34#include <linux/netfilter_ipv6.h>
35
36#include <net/sock.h>
37#include <net/snmp.h>
38
39#include <net/ipv6.h>
40#include <net/protocol.h>
41#include <net/transp_v6.h>
42#include <net/rawv6.h>
43#include <net/ndisc.h>
44#include <net/ip6_route.h>
45#include <net/addrconf.h>
46#include <net/xfrm.h>
47
48
49
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +090050inline int ip6_rcv_finish( struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -070051{
Eric Dumazetadf30902009-06-02 05:19:30 +000052 if (skb_dst(skb) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -070053 ip6_route_input(skb);
54
55 return dst_input(skb);
56}
57
David S. Millerf2ccd8f2005-08-09 19:34:12 -070058int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -070059{
Eric Dumazetb71d1d42011-04-22 04:53:02 +000060 const struct ipv6hdr *hdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 u32 pkt_len;
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +090062 struct inet6_dev *idev;
Denis V. Lunev483a47d2008-10-08 11:09:27 -070063 struct net *net = dev_net(skb->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +090065 if (skb->pkt_type == PACKET_OTHERHOST) {
66 kfree_skb(skb);
Mark Smith5c91fac2009-07-06 11:26:24 +000067 return NET_RX_DROP;
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +090068 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070069
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +090070 rcu_read_lock();
71
72 idev = __in6_dev_get(skb->dev);
73
Neil Hormanedf391f2009-04-27 02:45:02 -070074 IP6_UPD_PO_STATS_BH(net, idev, IPSTATS_MIB_IN, skb->len);
Linus Torvalds1da177e2005-04-16 15:20:36 -070075
YOSHIFUJI Hideaki778d80b2008-06-28 14:17:11 +090076 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL ||
77 !idev || unlikely(idev->cnf.disable_ipv6)) {
Denis V. Lunev483a47d2008-10-08 11:09:27 -070078 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INDISCARDS);
Jesper Nilsson71f6f6d2009-03-27 00:17:45 -070079 goto drop;
Linus Torvalds1da177e2005-04-16 15:20:36 -070080 }
81
Guillaume Chazarain6b7fdc32006-07-24 23:44:44 -070082 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
83
Linus Torvalds1da177e2005-04-16 15:20:36 -070084 /*
85 * Store incoming device index. When the packet will
86 * be queued, we cannot refer to skb->dev anymore.
87 *
88 * BTW, when we send a packet for our own local address on a
89 * non-loopback interface (e.g. ethX), it is being delivered
Daniel Lezcanode3cb742007-09-25 19:16:28 -070090 * via the loopback interface (lo) here; skb->dev = loopback_dev.
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 * It, however, should be considered as if it is being
92 * arrived via the sending interface (ethX), because of the
93 * nature of scoping architecture. --yoshfuji
94 */
Eric Dumazetadf30902009-06-02 05:19:30 +000095 IP6CB(skb)->iif = skb_dst(skb) ? ip6_dst_idev(skb_dst(skb))->dev->ifindex : dev->ifindex;
Linus Torvalds1da177e2005-04-16 15:20:36 -070096
Herbert Xu28891392006-06-30 13:35:46 -070097 if (unlikely(!pskb_may_pull(skb, sizeof(*hdr))))
Linus Torvalds1da177e2005-04-16 15:20:36 -070098 goto err;
99
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700100 hdr = ipv6_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101
102 if (hdr->version != 6)
103 goto err;
104
YOSHIFUJI Hideakif630e432008-06-19 16:33:57 -0700105 /*
106 * RFC4291 2.5.3
107 * A packet received on an interface with a destination address
108 * of loopback must be dropped.
109 */
110 if (!(dev->flags & IFF_LOOPBACK) &&
111 ipv6_addr_loopback(&hdr->daddr))
112 goto err;
113
Brian Haleyc4573382011-11-08 04:41:42 +0000114 /*
115 * RFC4291 2.7
116 * Multicast addresses must not be used as source addresses in IPv6
117 * packets or appear in any Routing header.
118 */
119 if (ipv6_addr_is_multicast(&hdr->saddr))
120 goto err;
121
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700122 skb->transport_header = skb->network_header + sizeof(*hdr);
Patrick McHardy951dbc82006-01-06 23:02:34 -0800123 IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);
124
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125 pkt_len = ntohs(hdr->payload_len);
126
127 /* pkt_len may be zero if Jumbo payload option is present */
128 if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
Mitsuru Chinen60e5c162007-04-04 23:54:59 -0700129 if (pkt_len + sizeof(struct ipv6hdr) > skb->len) {
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700130 IP6_INC_STATS_BH(net,
131 idev, IPSTATS_MIB_INTRUNCATEDPKTS);
Mitsuru Chinen60e5c162007-04-04 23:54:59 -0700132 goto drop;
133 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) {
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700135 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136 goto drop;
137 }
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700138 hdr = ipv6_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 }
140
141 if (hdr->nexthdr == NEXTHDR_HOP) {
Herbert Xue5bbef22007-10-15 12:50:28 -0700142 if (ipv6_parse_hopopts(skb) < 0) {
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700143 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INHDRERRORS);
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900144 rcu_read_unlock();
Mark Smith5c91fac2009-07-06 11:26:24 +0000145 return NET_RX_DROP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147 }
148
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900149 rcu_read_unlock();
150
Herbert Xu71f9dac2009-06-26 19:22:37 -0700151 /* Must drop socket now because of tproxy. */
152 skb_orphan(skb);
153
Jan Engelhardtb2e0b382010-03-23 04:09:07 +0100154 return NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, dev, NULL,
Patrick McHardy6e23ae22007-11-19 18:53:30 -0800155 ip6_rcv_finish);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156err:
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700157 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158drop:
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900159 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 kfree_skb(skb);
Mark Smith5c91fac2009-07-06 11:26:24 +0000161 return NET_RX_DROP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162}
163
164/*
165 * Deliver the packet to the host
166 */
167
168
Patrick McHardyad643a72007-10-15 01:51:38 -0700169static int ip6_input_finish(struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170{
Alexey Dobriyan41135cc2009-09-14 12:22:28 +0000171 const struct inet6_protocol *ipprot;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 unsigned int nhoff;
Pavel Emelyanov69d6da02007-11-19 22:35:57 -0800173 int nexthdr, raw;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 u8 hash;
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900175 struct inet6_dev *idev;
Eric Dumazetadf30902009-06-02 05:19:30 +0000176 struct net *net = dev_net(skb_dst(skb)->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178 /*
179 * Parse extension headers
180 */
181
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182 rcu_read_lock();
183resubmit:
Eric Dumazetadf30902009-06-02 05:19:30 +0000184 idev = ip6_dst_idev(skb_dst(skb));
Arnaldo Carvalho de Meloea2ae172007-04-25 17:55:53 -0700185 if (!pskb_pull(skb, skb_transport_offset(skb)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 goto discard;
Patrick McHardy951dbc82006-01-06 23:02:34 -0800187 nhoff = IP6CB(skb)->nhoff;
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700188 nexthdr = skb_network_header(skb)[nhoff];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189
Pavel Emelyanov69d6da02007-11-19 22:35:57 -0800190 raw = raw6_local_deliver(skb, nexthdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191
192 hash = nexthdr & (MAX_INET_PROTOS - 1);
193 if ((ipprot = rcu_dereference(inet6_protos[hash])) != NULL) {
194 int ret;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900195
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 if (ipprot->flags & INET6_PROTO_FINAL) {
Eric Dumazetb71d1d42011-04-22 04:53:02 +0000197 const struct ipv6hdr *hdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198
Yasuyuki Kozakai9fb9cbb2005-11-09 16:38:16 -0800199 /* Free reference early: we don't need it any more,
200 and it may hold ip_conntrack module loaded
201 indefinitely. */
202 nf_reset(skb);
203
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700204 skb_postpull_rcsum(skb, skb_network_header(skb),
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -0300205 skb_network_header_len(skb));
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700206 hdr = ipv6_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 if (ipv6_addr_is_multicast(&hdr->daddr) &&
208 !ipv6_chk_mcast_addr(skb->dev, &hdr->daddr,
209 &hdr->saddr) &&
210 !ipv6_is_mld(skb, nexthdr))
211 goto discard;
212 }
213 if (!(ipprot->flags & INET6_PROTO_NOPOLICY) &&
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900214 !xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 goto discard;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900216
Herbert Xue5bbef22007-10-15 12:50:28 -0700217 ret = ipprot->handler(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 if (ret > 0)
219 goto resubmit;
220 else if (ret == 0)
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700221 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INDELIVERS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 } else {
Pavel Emelyanov69d6da02007-11-19 22:35:57 -0800223 if (!raw) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 if (xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700225 IP6_INC_STATS_BH(net, idev,
226 IPSTATS_MIB_INUNKNOWNPROTOS);
Patrick McHardyfad87ac2005-08-16 21:03:41 -0700227 icmpv6_send(skb, ICMPV6_PARAMPROB,
Alexey Dobriyan3ffe5332010-02-18 08:25:24 +0000228 ICMPV6_UNK_NEXTHDR, nhoff);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229 }
Patrick McHardyfad87ac2005-08-16 21:03:41 -0700230 } else
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700231 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INDELIVERS);
Patrick McHardyfad87ac2005-08-16 21:03:41 -0700232 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 }
234 rcu_read_unlock();
235 return 0;
236
237discard:
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700238 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INDISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 rcu_read_unlock();
240 kfree_skb(skb);
241 return 0;
242}
243
244
245int ip6_input(struct sk_buff *skb)
246{
Jan Engelhardtb2e0b382010-03-23 04:09:07 +0100247 return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_IN, skb, skb->dev, NULL,
Patrick McHardy6e23ae22007-11-19 18:53:30 -0800248 ip6_input_finish);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249}
250
251int ip6_mc_input(struct sk_buff *skb)
252{
Eric Dumazetb71d1d42011-04-22 04:53:02 +0000253 const struct ipv6hdr *hdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 int deliver;
255
Eric Dumazetadf30902009-06-02 05:19:30 +0000256 IP6_UPD_PO_STATS_BH(dev_net(skb_dst(skb)->dev),
257 ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INMCAST,
Neil Hormanedf391f2009-04-27 02:45:02 -0700258 skb->len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700260 hdr = ipv6_hdr(skb);
YOSHIFUJI Hideaki4c7966b2008-03-31 19:30:45 -0700261 deliver = ipv6_chk_mcast_addr(skb->dev, &hdr->daddr, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900263#ifdef CONFIG_IPV6_MROUTE
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264 /*
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900265 * IPv6 multicast router mode is now supported ;)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266 */
YOSHIFUJI Hideaki53b79972008-07-19 22:35:03 -0700267 if (dev_net(skb->dev)->ipv6.devconf_all->mc_forwarding &&
Thomas Goff1d6e55f2009-01-27 22:39:59 -0800268 !(ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) &&
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900269 likely(!(IP6CB(skb)->flags & IP6SKB_FORWARDED))) {
270 /*
271 * Okay, we try to forward - split and duplicate
272 * packets.
273 */
274 struct sk_buff *skb2;
275 struct inet6_skb_parm *opt = IP6CB(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900277 /* Check for MLD */
278 if (unlikely(opt->ra)) {
279 /* Check if this is a mld message */
280 u8 *ptr = skb_network_header(skb) + opt->ra;
281 struct icmp6hdr *icmp6;
282 u8 nexthdr = hdr->nexthdr;
Jesse Gross75f28112011-11-30 17:05:51 -0800283 __be16 frag_off;
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900284 int offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900286 /* Check if the value of Router Alert
287 * is for MLD (0x0000).
288 */
289 if ((ptr[2] | ptr[3]) == 0) {
YOSHIFUJI Hideakiaba60962008-04-10 15:41:26 +0900290 deliver = 0;
291
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900292 if (!ipv6_ext_hdr(nexthdr)) {
293 /* BUG */
YOSHIFUJI Hideakiaba60962008-04-10 15:41:26 +0900294 goto out;
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900295 }
296 offset = ipv6_skip_exthdr(skb, sizeof(*hdr),
Jesse Gross75f28112011-11-30 17:05:51 -0800297 &nexthdr, &frag_off);
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900298 if (offset < 0)
YOSHIFUJI Hideakiaba60962008-04-10 15:41:26 +0900299 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900301 if (nexthdr != IPPROTO_ICMPV6)
YOSHIFUJI Hideakiaba60962008-04-10 15:41:26 +0900302 goto out;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900303
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900304 if (!pskb_may_pull(skb, (skb_network_header(skb) +
305 offset + 1 - skb->data)))
YOSHIFUJI Hideakiaba60962008-04-10 15:41:26 +0900306 goto out;
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900307
308 icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset);
309
310 switch (icmp6->icmp6_type) {
311 case ICMPV6_MGM_QUERY:
312 case ICMPV6_MGM_REPORT:
313 case ICMPV6_MGM_REDUCTION:
314 case ICMPV6_MLD2_REPORT:
YOSHIFUJI Hideakiaba60962008-04-10 15:41:26 +0900315 deliver = 1;
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900316 break;
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900317 }
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900318 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 }
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900320 /* unknown RA - process it normally */
321 }
322
323 if (deliver)
324 skb2 = skb_clone(skb, GFP_ATOMIC);
325 else {
326 skb2 = skb;
327 skb = NULL;
328 }
329
330 if (skb2) {
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900331 ip6_mr_input(skb2);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 }
333 }
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +0900334out:
YOSHIFUJI Hideakiaba60962008-04-10 15:41:26 +0900335#endif
336 if (likely(deliver))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 ip6_input(skb);
YOSHIFUJI Hideakiaba60962008-04-10 15:41:26 +0900338 else {
339 /* discard */
340 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342
343 return 0;
344}