[NETFILTER]: Add address family specific checksum helpers
Add checksum operation which takes care of verifying the checksum and
dealing with HW checksum errors and avoids multiple checksum
operations by setting ip_summed to CHECKSUM_UNNECESSARY after
successful verification.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h
index 6ee168c..b31a9bc 100644
--- a/include/linux/netfilter.h
+++ b/include/linux/netfilter.h
@@ -285,6 +285,8 @@
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 @@
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 43c09d7..85301c5 100644
--- a/include/linux/netfilter_ipv4.h
+++ b/include/linux/netfilter_ipv4.h
@@ -80,6 +80,8 @@
#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 14f2bd0..52a7b9e 100644
--- a/include/linux/netfilter_ipv6.h
+++ b/include/linux/netfilter_ipv6.h
@@ -73,6 +73,9 @@
};
#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 */