From 7be96f7628469e56f91d51f13b03e9bcff113c7f Mon Sep 17 00:00:00 2001 From: Masahide NAKAMURA Date: Wed, 23 Aug 2006 20:35:31 -0700 Subject: [PATCH] [IPV6] MIP6: Add receiving mobility header functions through raw socket. Like ICMPv6, mobility header is handled through raw socket. In inbound case, check only whether ICMPv6 error should be sent as a reply or not by kernel. Based on MIPL2 kernel patch. This patch was also written by: Ville Nuorvala This patch was also written by: Antti Tuominen Signed-off-by: Masahide NAKAMURA Signed-off-by: YOSHIFUJI Hideaki Signed-off-by: David S. Miller --- include/net/mip6.h | 4 +++ net/ipv6/mip6.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ net/ipv6/raw.c | 29 ++++++++++++++++++- 3 files changed, 115 insertions(+), 1 deletion(-) diff --git a/include/net/mip6.h b/include/net/mip6.h index fd43178..68263c6 100644 --- a/include/net/mip6.h +++ b/include/net/mip6.h @@ -25,6 +25,9 @@ #ifndef _NET_MIP6_H #define _NET_MIP6_H +#include +#include + #define MIP6_OPT_PAD_1 0 #define MIP6_OPT_PAD_N 1 @@ -53,5 +56,6 @@ struct ip6_mh { extern int mip6_init(void); extern void mip6_fini(void); +extern int mip6_mh_filter(struct sock *sk, struct sk_buff *skb); #endif diff --git a/net/ipv6/mip6.c b/net/ipv6/mip6.c index a8adf89..7b5f893 100644 --- a/net/ipv6/mip6.c +++ b/net/ipv6/mip6.c @@ -26,7 +26,10 @@ #include #include #include +#include +#include #include +#include #include #include @@ -55,6 +58,86 @@ static inline void *mip6_padn(__u8 *data, __u8 padlen) return data + padlen; } +static inline void mip6_param_prob(struct sk_buff *skb, int code, int pos) +{ + icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos, skb->dev); +} + +static int mip6_mh_len(int type) +{ + int len = 0; + + switch (type) { + case IP6_MH_TYPE_BRR: + len = 0; + break; + case IP6_MH_TYPE_HOTI: + case IP6_MH_TYPE_COTI: + case IP6_MH_TYPE_BU: + case IP6_MH_TYPE_BACK: + len = 1; + break; + case IP6_MH_TYPE_HOT: + case IP6_MH_TYPE_COT: + case IP6_MH_TYPE_BERROR: + len = 2; + break; + } + return len; +} + +int mip6_mh_filter(struct sock *sk, struct sk_buff *skb) +{ + struct ip6_mh *mh; + int mhlen; + + if (!pskb_may_pull(skb, (skb->h.raw - skb->data) + 8) || + !pskb_may_pull(skb, (skb->h.raw - skb->data) + ((skb->h.raw[1] + 1) << 3))) + return -1; + + mh = (struct ip6_mh *)skb->h.raw; + + if (mh->ip6mh_hdrlen < mip6_mh_len(mh->ip6mh_type)) { + LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH message too short: %d vs >=%d\n", + mh->ip6mh_hdrlen, mip6_mh_len(mh->ip6mh_type)); + mip6_param_prob(skb, 0, (&mh->ip6mh_hdrlen) - skb->nh.raw); + return -1; + } + mhlen = (mh->ip6mh_hdrlen + 1) << 3; + + if (skb->ip_summed == CHECKSUM_COMPLETE) { + skb->ip_summed = CHECKSUM_UNNECESSARY; + if (csum_ipv6_magic(&skb->nh.ipv6h->saddr, + &skb->nh.ipv6h->daddr, + mhlen, IPPROTO_MH, + skb->csum)) { + LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH hw checksum failed\n"); + skb->ip_summed = CHECKSUM_NONE; + } + } + if (skb->ip_summed == CHECKSUM_NONE) { + if (csum_ipv6_magic(&skb->nh.ipv6h->saddr, + &skb->nh.ipv6h->daddr, + mhlen, IPPROTO_MH, + skb_checksum(skb, 0, mhlen, 0))) { + LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH checksum failed [%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x > %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x]\n", + NIP6(skb->nh.ipv6h->saddr), + NIP6(skb->nh.ipv6h->daddr)); + return -1; + } + skb->ip_summed = CHECKSUM_UNNECESSARY; + } + + if (mh->ip6mh_proto != IPPROTO_NONE) { + LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n", + mh->ip6mh_proto); + mip6_param_prob(skb, 0, (&mh->ip6mh_proto) - skb->nh.raw); + return -1; + } + + return 0; +} + static int mip6_destopt_input(struct xfrm_state *x, struct sk_buff *skb) { struct ipv6hdr *iph = skb->nh.ipv6h; diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index d4af1cb..ecca8aa 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -50,6 +50,9 @@ #include #include #include +#ifdef CONFIG_IPV6_MIP6 +#include +#endif #include #include @@ -169,8 +172,32 @@ int ipv6_raw_deliver(struct sk_buff *skb, int nexthdr) sk = __raw_v6_lookup(sk, nexthdr, daddr, saddr, IP6CB(skb)->iif); while (sk) { + int filtered; + delivered = 1; - if (nexthdr != IPPROTO_ICMPV6 || !icmpv6_filter(sk, skb)) { + switch (nexthdr) { + case IPPROTO_ICMPV6: + filtered = icmpv6_filter(sk, skb); + break; +#ifdef CONFIG_IPV6_MIP6 + case IPPROTO_MH: + /* XXX: To validate MH only once for each packet, + * this is placed here. It should be after checking + * xfrm policy, however it doesn't. The checking xfrm + * policy is placed in rawv6_rcv() because it is + * required for each socket. + */ + filtered = mip6_mh_filter(sk, skb); + break; +#endif + default: + filtered = 0; + break; + } + + if (filtered < 0) + break; + if (filtered == 0) { struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC); /* Not releasing hash table! */ -- 2.7.4