271 lines
6.1 KiB
C
271 lines
6.1 KiB
C
/*
|
|
* 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/sched.h>
|
|
#include <linux/net.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/in6.h>
|
|
#include <linux/icmpv6.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>
|
|
|
|
|
|
|
|
static 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;
|
|
|
|
if (skb->pkt_type == PACKET_OTHERHOST)
|
|
goto drop;
|
|
|
|
IP6_INC_STATS_BH(IPSTATS_MIB_INRECEIVES);
|
|
|
|
if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
|
|
IP6_INC_STATS_BH(IPSTATS_MIB_INDISCARDS);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* 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 ? ((struct rt6_info *)skb->dst)->rt6i_idev->dev->ifindex : dev->ifindex;
|
|
|
|
if (skb->len < sizeof(struct ipv6hdr))
|
|
goto err;
|
|
|
|
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) {
|
|
IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
|
|
goto drop;
|
|
}
|
|
|
|
hdr = skb->nh.ipv6h;
|
|
|
|
if (hdr->version != 6)
|
|
goto err;
|
|
|
|
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)
|
|
goto truncated;
|
|
if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) {
|
|
IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
|
|
goto drop;
|
|
}
|
|
hdr = skb->nh.ipv6h;
|
|
}
|
|
|
|
if (hdr->nexthdr == NEXTHDR_HOP) {
|
|
skb->h.raw = (u8*)(hdr+1);
|
|
if (ipv6_parse_hopopts(skb, offsetof(struct ipv6hdr, nexthdr)) < 0) {
|
|
IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
|
|
return 0;
|
|
}
|
|
hdr = skb->nh.ipv6h;
|
|
}
|
|
|
|
return NF_HOOK(PF_INET6,NF_IP6_PRE_ROUTING, skb, dev, NULL, ip6_rcv_finish);
|
|
truncated:
|
|
IP6_INC_STATS_BH(IPSTATS_MIB_INTRUNCATEDPKTS);
|
|
err:
|
|
IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
|
|
drop:
|
|
kfree_skb(skb);
|
|
out:
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Deliver the packet to the host
|
|
*/
|
|
|
|
|
|
static inline int ip6_input_finish(struct sk_buff *skb)
|
|
{
|
|
struct inet6_protocol *ipprot;
|
|
struct sock *raw_sk;
|
|
unsigned int nhoff;
|
|
int nexthdr;
|
|
u8 hash;
|
|
|
|
skb->h.raw = skb->nh.raw + sizeof(struct ipv6hdr);
|
|
|
|
/*
|
|
* Parse extension headers
|
|
*/
|
|
|
|
nexthdr = skb->nh.ipv6h->nexthdr;
|
|
nhoff = offsetof(struct ipv6hdr, nexthdr);
|
|
|
|
/* Skip hop-by-hop options, they are already parsed. */
|
|
if (nexthdr == NEXTHDR_HOP) {
|
|
nhoff = sizeof(struct ipv6hdr);
|
|
nexthdr = skb->h.raw[0];
|
|
skb->h.raw += (skb->h.raw[1]+1)<<3;
|
|
}
|
|
|
|
rcu_read_lock();
|
|
resubmit:
|
|
if (!pskb_pull(skb, skb->h.raw - skb->data))
|
|
goto discard;
|
|
nexthdr = skb->nh.raw[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;
|
|
|
|
skb_postpull_rcsum(skb, skb->nh.raw,
|
|
skb->h.raw - skb->nh.raw);
|
|
hdr = skb->nh.ipv6h;
|
|
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, &nhoff);
|
|
if (ret > 0)
|
|
goto resubmit;
|
|
else if (ret == 0)
|
|
IP6_INC_STATS_BH(IPSTATS_MIB_INDELIVERS);
|
|
} else {
|
|
if (!raw_sk) {
|
|
if (xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
|
|
IP6_INC_STATS_BH(IPSTATS_MIB_INUNKNOWNPROTOS);
|
|
icmpv6_send(skb, ICMPV6_PARAMPROB,
|
|
ICMPV6_UNK_NEXTHDR, nhoff,
|
|
skb->dev);
|
|
}
|
|
} else
|
|
IP6_INC_STATS_BH(IPSTATS_MIB_INDELIVERS);
|
|
kfree_skb(skb);
|
|
}
|
|
rcu_read_unlock();
|
|
return 0;
|
|
|
|
discard:
|
|
IP6_INC_STATS_BH(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(IPSTATS_MIB_INMCASTPKTS);
|
|
|
|
hdr = skb->nh.ipv6h;
|
|
deliver = likely(!(skb->dev->flags & (IFF_PROMISC|IFF_ALLMULTI))) ||
|
|
ipv6_chk_mcast_addr(skb->dev, &hdr->daddr, NULL);
|
|
|
|
/*
|
|
* IPv6 multicast router mode isnt currently supported.
|
|
*/
|
|
#if 0
|
|
if (ipv6_config.multicast_route) {
|
|
int addr_type;
|
|
|
|
addr_type = ipv6_addr_type(&hdr->daddr);
|
|
|
|
if (!(addr_type & (IPV6_ADDR_LOOPBACK | IPV6_ADDR_LINKLOCAL))) {
|
|
struct sk_buff *skb2;
|
|
struct dst_entry *dst;
|
|
|
|
dst = skb->dst;
|
|
|
|
if (deliver) {
|
|
skb2 = skb_clone(skb, GFP_ATOMIC);
|
|
dst_output(skb2);
|
|
} else {
|
|
dst_output(skb);
|
|
return 0;
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (likely(deliver)) {
|
|
ip6_input(skb);
|
|
return 0;
|
|
}
|
|
/* discard */
|
|
kfree_skb(skb);
|
|
|
|
return 0;
|
|
}
|