diff options
Diffstat (limited to 'net/ipv6/ip6_input.c')
| -rw-r--r-- | net/ipv6/ip6_input.c | 269 |
1 files changed, 269 insertions, 0 deletions
diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c new file mode 100644 index 00000000000..866f10726c5 --- /dev/null +++ b/net/ipv6/ip6_input.c @@ -0,0 +1,269 @@ +/* + * 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 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); + + 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_param_prob(skb, ICMPV6_UNK_NEXTHDR, nhoff); + } + } 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; +} |