/release/src-rt/linux/linux-2.6/net/ipv6/ip6_input.c
C | 322 lines | 211 code | 52 blank | 59 comment | 47 complexity | f9d18b248a14d5d909297fe3933b8cd5 MD5 | raw file
- /*
- * IPv6 input
- * Linux INET6 implementation
- *
- * Authors:
- * Pedro Roque <roque@di.fc.ul.pt>
- * Ian P. Morris <I.P.Morris@soton.ac.uk>
- *
- * $Id: ip6_input.c,v 1.19 2000/12/13 18:31:50 davem Exp $
- *
- * Based in linux/net/ipv4/ip_input.c
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
- /* Changes
- *
- * Mitsuru KANDA @USAGI and
- * YOSHIFUJI Hideaki @USAGI: Remove ipv6_parse_exthdrs().
- */
- #include <linux/errno.h>
- #include <linux/types.h>
- #include <linux/socket.h>
- #include <linux/sockios.h>
- #include <linux/net.h>
- #include <linux/netdevice.h>
- #include <linux/in6.h>
- #include <linux/icmpv6.h>
- #include <linux/mroute6.h>
- #include <linux/netfilter.h>
- #include <linux/netfilter_ipv6.h>
- #include <net/sock.h>
- #include <net/snmp.h>
- #include <net/ipv6.h>
- #include <net/protocol.h>
- #include <net/transp_v6.h>
- #include <net/rawv6.h>
- #include <net/ndisc.h>
- #include <net/ip6_route.h>
- #include <net/addrconf.h>
- #include <net/xfrm.h>
- inline int ip6_rcv_finish( struct sk_buff *skb)
- {
- if (skb->dst == NULL)
- ip6_route_input(skb);
- return dst_input(skb);
- }
- int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
- {
- struct ipv6hdr *hdr;
- u32 pkt_len;
- struct inet6_dev *idev;
- if (skb->pkt_type == PACKET_OTHERHOST) {
- kfree_skb(skb);
- return 0;
- }
- rcu_read_lock();
- idev = __in6_dev_get(skb->dev);
- IP6_INC_STATS_BH(idev, IPSTATS_MIB_INRECEIVES);
- if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL ||
- !idev || unlikely(idev->cnf.disable_ipv6)) {
- IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDISCARDS);
- goto drop;
- }
- memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
- /*
- * Store incoming device index. When the packet will
- * be queued, we cannot refer to skb->dev anymore.
- *
- * BTW, when we send a packet for our own local address on a
- * non-loopback interface (e.g. ethX), it is being delivered
- * via the loopback interface (lo) here; skb->dev = &loopback_dev.
- * It, however, should be considered as if it is being
- * arrived via the sending interface (ethX), because of the
- * nature of scoping architecture. --yoshfuji
- */
- IP6CB(skb)->iif = skb->dst ? ip6_dst_idev(skb->dst)->dev->ifindex : dev->ifindex;
- if (unlikely(!pskb_may_pull(skb, sizeof(*hdr))))
- goto err;
- hdr = ipv6_hdr(skb);
- if (hdr->version != 6)
- goto err;
- skb->transport_header = skb->network_header + sizeof(*hdr);
- IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);
- pkt_len = ntohs(hdr->payload_len);
- /* pkt_len may be zero if Jumbo payload option is present */
- if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
- if (pkt_len + sizeof(struct ipv6hdr) > skb->len) {
- IP6_INC_STATS_BH(idev, IPSTATS_MIB_INTRUNCATEDPKTS);
- goto drop;
- }
- if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) {
- IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS);
- goto drop;
- }
- hdr = ipv6_hdr(skb);
- }
- if (hdr->nexthdr == NEXTHDR_HOP) {
- if (ipv6_parse_hopopts(skb) < 0) {
- IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS);
- rcu_read_unlock();
- return 0;
- }
- }
- rcu_read_unlock();
- return NF_HOOK(PF_INET6,NF_IP6_PRE_ROUTING, skb, dev, NULL, ip6_rcv_finish);
- err:
- IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS);
- drop:
- rcu_read_unlock();
- kfree_skb(skb);
- return 0;
- }
- /*
- * Deliver the packet to the host
- */
- static int ip6_input_finish(struct sk_buff *skb)
- {
- struct inet6_protocol *ipprot;
- struct sock *raw_sk;
- unsigned int nhoff;
- int nexthdr;
- u8 hash;
- struct inet6_dev *idev;
- /*
- * Parse extension headers
- */
- rcu_read_lock();
- resubmit:
- idev = ip6_dst_idev(skb->dst);
- if (!pskb_pull(skb, skb_transport_offset(skb)))
- goto discard;
- nhoff = IP6CB(skb)->nhoff;
- nexthdr = skb_network_header(skb)[nhoff];
- raw_sk = sk_head(&raw_v6_htable[nexthdr & (MAX_INET_PROTOS - 1)]);
- if (raw_sk && !ipv6_raw_deliver(skb, nexthdr))
- raw_sk = NULL;
- hash = nexthdr & (MAX_INET_PROTOS - 1);
- if ((ipprot = rcu_dereference(inet6_protos[hash])) != NULL) {
- int ret;
- if (ipprot->flags & INET6_PROTO_FINAL) {
- struct ipv6hdr *hdr;
- /* Free reference early: we don't need it any more,
- and it may hold ip_conntrack module loaded
- indefinitely. */
- nf_reset(skb);
- skb_postpull_rcsum(skb, skb_network_header(skb),
- skb_network_header_len(skb));
- hdr = ipv6_hdr(skb);
- if (ipv6_addr_is_multicast(&hdr->daddr) &&
- !ipv6_chk_mcast_addr(skb->dev, &hdr->daddr,
- &hdr->saddr) &&
- !ipv6_is_mld(skb, nexthdr))
- goto discard;
- }
- if (!(ipprot->flags & INET6_PROTO_NOPOLICY) &&
- !xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
- goto discard;
- ret = ipprot->handler(skb);
- if (ret > 0)
- goto resubmit;
- else if (ret == 0)
- IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDELIVERS);
- } else {
- if (!raw_sk) {
- if (xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
- IP6_INC_STATS_BH(idev, IPSTATS_MIB_INUNKNOWNPROTOS);
- icmpv6_send(skb, ICMPV6_PARAMPROB,
- ICMPV6_UNK_NEXTHDR, nhoff,
- skb->dev);
- }
- } else
- IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDELIVERS);
- kfree_skb(skb);
- }
- rcu_read_unlock();
- return 0;
- discard:
- IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDISCARDS);
- rcu_read_unlock();
- kfree_skb(skb);
- return 0;
- }
- int ip6_input(struct sk_buff *skb)
- {
- return NF_HOOK(PF_INET6,NF_IP6_LOCAL_IN, skb, skb->dev, NULL, ip6_input_finish);
- }
- int ip6_mc_input(struct sk_buff *skb)
- {
- struct ipv6hdr *hdr;
- int deliver;
- IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INMCASTPKTS);
- hdr = ipv6_hdr(skb);
- deliver = ipv6_chk_mcast_addr(skb->dev, &hdr->daddr, NULL);
- #ifdef CONFIG_IPV6_MROUTE
- /*
- * IPv6 multicast router mode is now supported ;)
- */
- if (ipv6_devconf.mc_forwarding &&
- likely(!(IP6CB(skb)->flags & IP6SKB_FORWARDED))) {
- /*
- * Okay, we try to forward - split and duplicate
- * packets.
- */
- struct sk_buff *skb2;
- struct inet6_skb_parm *opt = IP6CB(skb);
- /* Check for MLD */
- if (unlikely(opt->ra)) {
- /* Check if this is a mld message */
- u8 *ptr = skb_network_header(skb) + opt->ra;
- struct icmp6hdr *icmp6;
- u8 nexthdr = hdr->nexthdr;
- int offset;
- /* Check if the value of Router Alert
- * is for MLD (0x0000).
- */
- if ((ptr[2] | ptr[3]) == 0) {
- if (!ipv6_ext_hdr(nexthdr)) {
- /* BUG */
- goto discard;
- }
- offset = ipv6_skip_exthdr(skb, sizeof(*hdr),
- &nexthdr);
- if (offset < 0)
- goto discard;
- if (nexthdr != IPPROTO_ICMPV6)
- goto discard;
- if (!pskb_may_pull(skb, (skb_network_header(skb) +
- offset + 1 - skb->data)))
- goto discard;
- icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset);
- switch (icmp6->icmp6_type) {
- case ICMPV6_MGM_QUERY:
- case ICMPV6_MGM_REPORT:
- case ICMPV6_MGM_REDUCTION:
- case ICMPV6_MLD2_REPORT:
- break;
- default:
- /* Bogus */
- goto discard;
- }
- deliver = 1;
- goto out;
- }
- /* unknown RA - process it normally */
- }
- if (deliver)
- skb2 = skb_clone(skb, GFP_ATOMIC);
- else {
- skb2 = skb;
- skb = NULL;
- }
- if (skb2) {
- skb2->dev = skb2->dst->dev;
- ip6_mr_input(skb2);
- }
- }
- out:
- #endif
- if (likely(deliver)) {
- ip6_input(skb);
- return 0;
- }
- discard:
- /* discard */
- kfree_skb(skb);
- return 0;
- }