blob: 98ab4f459905dce22f29a46450157a7ba8623f32 [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 *
9 * $Id: ip6_input.c,v 1.19 2000/12/13 18:31:50 davem Exp $
10 *
11 * Based in linux/net/ipv4/ip_input.c
12 *
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version
16 * 2 of the License, or (at your option) any later version.
17 */
18/* Changes
19 *
20 * Mitsuru KANDA @USAGI and
21 * YOSHIFUJI Hideaki @USAGI: Remove ipv6_parse_exthdrs().
22 */
23
24#include <linux/errno.h>
25#include <linux/types.h>
26#include <linux/socket.h>
27#include <linux/sockios.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include <linux/net.h>
29#include <linux/netdevice.h>
30#include <linux/in6.h>
31#include <linux/icmpv6.h>
32
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{
52 if (skb->dst == NULL)
53 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{
60 struct ipv6hdr *hdr;
61 u32 pkt_len;
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +090062 struct inet6_dev *idev;
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
Eric W. Biedermane730c152007-09-17 11:53:39 -070064 if (dev->nd_net != &init_net) {
65 kfree_skb(skb);
66 return 0;
67 }
68
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +090069 if (skb->pkt_type == PACKET_OTHERHOST) {
70 kfree_skb(skb);
71 return 0;
72 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +090074 rcu_read_lock();
75
76 idev = __in6_dev_get(skb->dev);
77
78 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INRECEIVES);
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
80 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +090081 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDISCARDS);
82 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -070083 goto out;
84 }
85
Guillaume Chazarain6b7fdc32006-07-24 23:44:44 -070086 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
87
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 /*
89 * Store incoming device index. When the packet will
90 * be queued, we cannot refer to skb->dev anymore.
91 *
92 * BTW, when we send a packet for our own local address on a
93 * non-loopback interface (e.g. ethX), it is being delivered
Daniel Lezcanode3cb742007-09-25 19:16:28 -070094 * via the loopback interface (lo) here; skb->dev = loopback_dev.
Linus Torvalds1da177e2005-04-16 15:20:36 -070095 * It, however, should be considered as if it is being
96 * arrived via the sending interface (ethX), because of the
97 * nature of scoping architecture. --yoshfuji
98 */
YOSHIFUJI Hideaki7a3025b2006-10-13 16:17:25 +090099 IP6CB(skb)->iif = skb->dst ? ip6_dst_idev(skb->dst)->dev->ifindex : dev->ifindex;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100
Herbert Xu28891392006-06-30 13:35:46 -0700101 if (unlikely(!pskb_may_pull(skb, sizeof(*hdr))))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 goto err;
103
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700104 hdr = ipv6_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105
106 if (hdr->version != 6)
107 goto err;
108
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700109 skb->transport_header = skb->network_header + sizeof(*hdr);
Patrick McHardy951dbc82006-01-06 23:02:34 -0800110 IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);
111
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 pkt_len = ntohs(hdr->payload_len);
113
114 /* pkt_len may be zero if Jumbo payload option is present */
115 if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
Mitsuru Chinen60e5c162007-04-04 23:54:59 -0700116 if (pkt_len + sizeof(struct ipv6hdr) > skb->len) {
117 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INTRUNCATEDPKTS);
118 goto drop;
119 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) {
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900121 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 goto drop;
123 }
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700124 hdr = ipv6_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125 }
126
127 if (hdr->nexthdr == NEXTHDR_HOP) {
Herbert Xue5bbef22007-10-15 12:50:28 -0700128 if (ipv6_parse_hopopts(skb) < 0) {
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900129 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS);
130 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131 return 0;
132 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133 }
134
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900135 rcu_read_unlock();
136
Patrick McHardy6e23ae22007-11-19 18:53:30 -0800137 return NF_HOOK(PF_INET6, NF_INET_PRE_ROUTING, skb, dev, NULL,
138 ip6_rcv_finish);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139err:
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900140 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141drop:
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900142 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143 kfree_skb(skb);
144out:
145 return 0;
146}
147
148/*
149 * Deliver the packet to the host
150 */
151
152
Patrick McHardyad643a72007-10-15 01:51:38 -0700153static int ip6_input_finish(struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154{
155 struct inet6_protocol *ipprot;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156 unsigned int nhoff;
Pavel Emelyanov69d6da02007-11-19 22:35:57 -0800157 int nexthdr, raw;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 u8 hash;
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900159 struct inet6_dev *idev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161 /*
162 * Parse extension headers
163 */
164
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165 rcu_read_lock();
166resubmit:
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900167 idev = ip6_dst_idev(skb->dst);
Arnaldo Carvalho de Meloea2ae172007-04-25 17:55:53 -0700168 if (!pskb_pull(skb, skb_transport_offset(skb)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 goto discard;
Patrick McHardy951dbc82006-01-06 23:02:34 -0800170 nhoff = IP6CB(skb)->nhoff;
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700171 nexthdr = skb_network_header(skb)[nhoff];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172
Pavel Emelyanov69d6da02007-11-19 22:35:57 -0800173 raw = raw6_local_deliver(skb, nexthdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174
175 hash = nexthdr & (MAX_INET_PROTOS - 1);
176 if ((ipprot = rcu_dereference(inet6_protos[hash])) != NULL) {
177 int ret;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900178
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 if (ipprot->flags & INET6_PROTO_FINAL) {
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900180 struct ipv6hdr *hdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181
Yasuyuki Kozakai9fb9cbb2005-11-09 16:38:16 -0800182 /* Free reference early: we don't need it any more,
183 and it may hold ip_conntrack module loaded
184 indefinitely. */
185 nf_reset(skb);
186
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700187 skb_postpull_rcsum(skb, skb_network_header(skb),
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -0300188 skb_network_header_len(skb));
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700189 hdr = ipv6_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 if (ipv6_addr_is_multicast(&hdr->daddr) &&
191 !ipv6_chk_mcast_addr(skb->dev, &hdr->daddr,
192 &hdr->saddr) &&
193 !ipv6_is_mld(skb, nexthdr))
194 goto discard;
195 }
196 if (!(ipprot->flags & INET6_PROTO_NOPOLICY) &&
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900197 !xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 goto discard;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900199
Herbert Xue5bbef22007-10-15 12:50:28 -0700200 ret = ipprot->handler(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 if (ret > 0)
202 goto resubmit;
203 else if (ret == 0)
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900204 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDELIVERS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205 } else {
Pavel Emelyanov69d6da02007-11-19 22:35:57 -0800206 if (!raw) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 if (xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900208 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INUNKNOWNPROTOS);
Patrick McHardyfad87ac2005-08-16 21:03:41 -0700209 icmpv6_send(skb, ICMPV6_PARAMPROB,
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900210 ICMPV6_UNK_NEXTHDR, nhoff,
211 skb->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212 }
Patrick McHardyfad87ac2005-08-16 21:03:41 -0700213 } else
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900214 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDELIVERS);
Patrick McHardyfad87ac2005-08-16 21:03:41 -0700215 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 }
217 rcu_read_unlock();
218 return 0;
219
220discard:
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900221 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 rcu_read_unlock();
223 kfree_skb(skb);
224 return 0;
225}
226
227
228int ip6_input(struct sk_buff *skb)
229{
Patrick McHardy6e23ae22007-11-19 18:53:30 -0800230 return NF_HOOK(PF_INET6, NF_INET_LOCAL_IN, skb, skb->dev, NULL,
231 ip6_input_finish);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232}
233
234int ip6_mc_input(struct sk_buff *skb)
235{
236 struct ipv6hdr *hdr;
237 int deliver;
238
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900239 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INMCASTPKTS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700241 hdr = ipv6_hdr(skb);
YOSHIFUJI Hideaki4c7966b2008-03-31 19:30:45 -0700242 deliver = ipv6_chk_mcast_addr(skb->dev, &hdr->daddr, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243
244 /*
245 * IPv6 multicast router mode isnt currently supported.
246 */
247#if 0
248 if (ipv6_config.multicast_route) {
249 int addr_type;
250
251 addr_type = ipv6_addr_type(&hdr->daddr);
252
253 if (!(addr_type & (IPV6_ADDR_LOOPBACK | IPV6_ADDR_LINKLOCAL))) {
254 struct sk_buff *skb2;
255 struct dst_entry *dst;
256
257 dst = skb->dst;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900258
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259 if (deliver) {
260 skb2 = skb_clone(skb, GFP_ATOMIC);
261 dst_output(skb2);
262 } else {
263 dst_output(skb);
264 return 0;
265 }
266 }
267 }
268#endif
269
270 if (likely(deliver)) {
271 ip6_input(skb);
272 return 0;
273 }
274 /* discard */
275 kfree_skb(skb);
276
277 return 0;
278}