3 * Linux INET6 implementation
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Ian P. Morris <I.P.Morris@soton.ac.uk>
9 * Based in linux/net/ipv4/ip_input.c
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.
18 * Mitsuru KANDA @USAGI and
19 * YOSHIFUJI Hideaki @USAGI: Remove ipv6_parse_exthdrs().
22 #include <linux/errno.h>
23 #include <linux/types.h>
24 #include <linux/socket.h>
25 #include <linux/sockios.h>
26 #include <linux/net.h>
27 #include <linux/netdevice.h>
28 #include <linux/in6.h>
29 #include <linux/icmpv6.h>
30 #include <linux/mroute6.h>
32 #include <linux/netfilter.h>
33 #include <linux/netfilter_ipv6.h>
39 #include <net/protocol.h>
40 #include <net/transp_v6.h>
41 #include <net/rawv6.h>
42 #include <net/ndisc.h>
43 #include <net/ip6_route.h>
44 #include <net/addrconf.h>
49 inline int ip6_rcv_finish( struct sk_buff *skb)
54 return dst_input(skb);
57 int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
61 struct inet6_dev *idev;
63 if (skb->pkt_type == PACKET_OTHERHOST) {
70 idev = __in6_dev_get(skb->dev);
72 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INRECEIVES);
74 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL ||
75 !idev || unlikely(idev->cnf.disable_ipv6)) {
76 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDISCARDS);
81 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
84 * Store incoming device index. When the packet will
85 * be queued, we cannot refer to skb->dev anymore.
87 * BTW, when we send a packet for our own local address on a
88 * non-loopback interface (e.g. ethX), it is being delivered
89 * via the loopback interface (lo) here; skb->dev = loopback_dev.
90 * It, however, should be considered as if it is being
91 * arrived via the sending interface (ethX), because of the
92 * nature of scoping architecture. --yoshfuji
94 IP6CB(skb)->iif = skb->dst ? ip6_dst_idev(skb->dst)->dev->ifindex : dev->ifindex;
96 if (unlikely(!pskb_may_pull(skb, sizeof(*hdr))))
101 if (hdr->version != 6)
106 * A packet received on an interface with a destination address
107 * of loopback must be dropped.
109 if (!(dev->flags & IFF_LOOPBACK) &&
110 ipv6_addr_loopback(&hdr->daddr))
113 skb->transport_header = skb->network_header + sizeof(*hdr);
114 IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);
116 pkt_len = ntohs(hdr->payload_len);
118 /* pkt_len may be zero if Jumbo payload option is present */
119 if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
120 if (pkt_len + sizeof(struct ipv6hdr) > skb->len) {
121 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INTRUNCATEDPKTS);
124 if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) {
125 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS);
131 if (hdr->nexthdr == NEXTHDR_HOP) {
132 if (ipv6_parse_hopopts(skb) < 0) {
133 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS);
141 return NF_HOOK(PF_INET6, NF_INET_PRE_ROUTING, skb, dev, NULL,
144 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS);
153 * Deliver the packet to the host
157 static int ip6_input_finish(struct sk_buff *skb)
159 struct inet6_protocol *ipprot;
163 struct inet6_dev *idev;
166 * Parse extension headers
171 idev = ip6_dst_idev(skb->dst);
172 if (!pskb_pull(skb, skb_transport_offset(skb)))
174 nhoff = IP6CB(skb)->nhoff;
175 nexthdr = skb_network_header(skb)[nhoff];
177 raw = raw6_local_deliver(skb, nexthdr);
179 hash = nexthdr & (MAX_INET_PROTOS - 1);
180 if ((ipprot = rcu_dereference(inet6_protos[hash])) != NULL) {
183 if (ipprot->flags & INET6_PROTO_FINAL) {
186 /* Free reference early: we don't need it any more,
187 and it may hold ip_conntrack module loaded
191 skb_postpull_rcsum(skb, skb_network_header(skb),
192 skb_network_header_len(skb));
194 if (ipv6_addr_is_multicast(&hdr->daddr) &&
195 !ipv6_chk_mcast_addr(skb->dev, &hdr->daddr,
197 !ipv6_is_mld(skb, nexthdr))
200 if (!(ipprot->flags & INET6_PROTO_NOPOLICY) &&
201 !xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
204 ret = ipprot->handler(skb);
208 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDELIVERS);
211 if (xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
212 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INUNKNOWNPROTOS);
213 icmpv6_send(skb, ICMPV6_PARAMPROB,
214 ICMPV6_UNK_NEXTHDR, nhoff,
218 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDELIVERS);
225 IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDISCARDS);
232 int ip6_input(struct sk_buff *skb)
234 return NF_HOOK(PF_INET6, NF_INET_LOCAL_IN, skb, skb->dev, NULL,
238 int ip6_mc_input(struct sk_buff *skb)
243 IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INMCASTPKTS);
246 deliver = ipv6_chk_mcast_addr(skb->dev, &hdr->daddr, NULL);
248 #ifdef CONFIG_IPV6_MROUTE
250 * IPv6 multicast router mode is now supported ;)
252 if (dev_net(skb->dev)->ipv6.devconf_all->mc_forwarding &&
253 likely(!(IP6CB(skb)->flags & IP6SKB_FORWARDED))) {
255 * Okay, we try to forward - split and duplicate
258 struct sk_buff *skb2;
259 struct inet6_skb_parm *opt = IP6CB(skb);
262 if (unlikely(opt->ra)) {
263 /* Check if this is a mld message */
264 u8 *ptr = skb_network_header(skb) + opt->ra;
265 struct icmp6hdr *icmp6;
266 u8 nexthdr = hdr->nexthdr;
269 /* Check if the value of Router Alert
270 * is for MLD (0x0000).
272 if ((ptr[2] | ptr[3]) == 0) {
275 if (!ipv6_ext_hdr(nexthdr)) {
279 offset = ipv6_skip_exthdr(skb, sizeof(*hdr),
284 if (nexthdr != IPPROTO_ICMPV6)
287 if (!pskb_may_pull(skb, (skb_network_header(skb) +
288 offset + 1 - skb->data)))
291 icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset);
293 switch (icmp6->icmp6_type) {
294 case ICMPV6_MGM_QUERY:
295 case ICMPV6_MGM_REPORT:
296 case ICMPV6_MGM_REDUCTION:
297 case ICMPV6_MLD2_REPORT:
303 /* unknown RA - process it normally */
307 skb2 = skb_clone(skb, GFP_ATOMIC);
314 skb2->dev = skb2->dst->dev;