diff options
| -rw-r--r-- | include/linux/netfilter.h | 17 | ||||
| -rw-r--r-- | include/linux/netfilter_ipv4.h | 2 | ||||
| -rw-r--r-- | include/linux/netfilter_ipv6.h | 3 | ||||
| -rw-r--r-- | net/ipv4/netfilter.c | 33 | ||||
| -rw-r--r-- | net/ipv6/netfilter.c | 34 |
5 files changed, 89 insertions, 0 deletions
diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h index 6ee168c4978..b31a9bca936 100644 --- a/include/linux/netfilter.h +++ b/include/linux/netfilter.h @@ -285,6 +285,8 @@ extern int skb_make_writable(struct sk_buff **pskb, unsigned int writable_len); struct nf_afinfo { unsigned short family; + unsigned int (*checksum)(struct sk_buff *skb, unsigned int hook, + unsigned int dataoff, u_int8_t protocol); void (*saveroute)(const struct sk_buff *skb, struct nf_info *info); int (*reroute)(struct sk_buff **skb, @@ -298,6 +300,21 @@ static inline struct nf_afinfo *nf_get_afinfo(unsigned short family) return rcu_dereference(nf_afinfo[family]); } +static inline unsigned int +nf_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff, + u_int8_t protocol, unsigned short family) +{ + struct nf_afinfo *afinfo; + unsigned int csum = 0; + + rcu_read_lock(); + afinfo = nf_get_afinfo(family); + if (afinfo) + csum = afinfo->checksum(skb, hook, dataoff, protocol); + rcu_read_unlock(); + return csum; +} + extern int nf_register_afinfo(struct nf_afinfo *afinfo); extern void nf_unregister_afinfo(struct nf_afinfo *afinfo); diff --git a/include/linux/netfilter_ipv4.h b/include/linux/netfilter_ipv4.h index 43c09d790b8..85301c5e8d2 100644 --- a/include/linux/netfilter_ipv4.h +++ b/include/linux/netfilter_ipv4.h @@ -80,6 +80,8 @@ enum nf_ip_hook_priorities { #ifdef __KERNEL__ extern int ip_route_me_harder(struct sk_buff **pskb); extern int ip_xfrm_me_harder(struct sk_buff **pskb); +extern unsigned int nf_ip_checksum(struct sk_buff *skb, unsigned int hook, + unsigned int dataoff, u_int8_t protocol); #endif /*__KERNEL__*/ #endif /*__LINUX_IP_NETFILTER_H*/ diff --git a/include/linux/netfilter_ipv6.h b/include/linux/netfilter_ipv6.h index 14f2bd01088..52a7b9e7642 100644 --- a/include/linux/netfilter_ipv6.h +++ b/include/linux/netfilter_ipv6.h @@ -73,6 +73,9 @@ enum nf_ip6_hook_priorities { }; #ifdef CONFIG_NETFILTER +extern unsigned int nf_ip6_checksum(struct sk_buff *skb, unsigned int hook, + unsigned int dataoff, u_int8_t protocol); + extern int ipv6_netfilter_init(void); extern void ipv6_netfilter_fini(void); #else /* CONFIG_NETFILTER */ diff --git a/net/ipv4/netfilter.c b/net/ipv4/netfilter.c index b25339c11ea..6a9e34b794b 100644 --- a/net/ipv4/netfilter.c +++ b/net/ipv4/netfilter.c @@ -161,8 +161,41 @@ static int nf_ip_reroute(struct sk_buff **pskb, const struct nf_info *info) return 0; } +unsigned int nf_ip_checksum(struct sk_buff *skb, unsigned int hook, + unsigned int dataoff, u_int8_t protocol) +{ + struct iphdr *iph = skb->nh.iph; + unsigned int csum = 0; + + switch (skb->ip_summed) { + case CHECKSUM_HW: + if (hook != NF_IP_PRE_ROUTING && hook != NF_IP_LOCAL_IN) + break; + if ((protocol == 0 && !(u16)csum_fold(skb->csum)) || + !csum_tcpudp_magic(iph->saddr, iph->daddr, + skb->len - dataoff, protocol, + skb->csum)) { + skb->ip_summed = CHECKSUM_UNNECESSARY; + break; + } + /* fall through */ + case CHECKSUM_NONE: + if (protocol == 0) + skb->csum = 0; + else + skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr, + skb->len - dataoff, + protocol, 0); + csum = __skb_checksum_complete(skb); + } + return csum; +} + +EXPORT_SYMBOL(nf_ip_checksum); + static struct nf_afinfo nf_ip_afinfo = { .family = AF_INET, + .checksum = nf_ip_checksum, .saveroute = nf_ip_saveroute, .reroute = nf_ip_reroute, .route_key_size = sizeof(struct ip_rt_info), diff --git a/net/ipv6/netfilter.c b/net/ipv6/netfilter.c index f514a0113b9..3e9ecfaf67e 100644 --- a/net/ipv6/netfilter.c +++ b/net/ipv6/netfilter.c @@ -79,8 +79,42 @@ static int nf_ip6_reroute(struct sk_buff **pskb, const struct nf_info *info) return 0; } +unsigned int nf_ip6_checksum(struct sk_buff *skb, unsigned int hook, + unsigned int dataoff, u_int8_t protocol) +{ + struct ipv6hdr *ip6h = skb->nh.ipv6h; + unsigned int csum = 0; + + switch (skb->ip_summed) { + case CHECKSUM_HW: + if (hook != NF_IP6_PRE_ROUTING && hook != NF_IP6_LOCAL_IN) + break; + if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, + skb->len - dataoff, protocol, + csum_sub(skb->csum, + skb_checksum(skb, 0, + dataoff, 0)))) { + skb->ip_summed = CHECKSUM_UNNECESSARY; + break; + } + /* fall through */ + case CHECKSUM_NONE: + skb->csum = ~csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, + skb->len - dataoff, + protocol, + csum_sub(0, + skb_checksum(skb, 0, + dataoff, 0))); + csum = __skb_checksum_complete(skb); + } + return csum; +} + +EXPORT_SYMBOL(nf_ip6_checksum); + static struct nf_afinfo nf_ip6_afinfo = { .family = AF_INET6, + .checksum = nf_ip6_checksum, .saveroute = nf_ip6_saveroute, .reroute = nf_ip6_reroute, .route_key_size = sizeof(struct ip6_rt_info), |