[NETFILTER]: Add partial checksum validation helper

[net-next-2.6.git] / include / linux / netfilter.h

diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h
index 66bc52060fd63f3bf759505cd5cc923965a11332..e4c66593b5c697f32d140cdc34a121c1173425d9 100644 (file)
--- a/include/linux/netfilter.h
+++ b/include/linux/netfilter.h
@@ -234,6 +234,11 @@ struct nf_afinfo {
        unsigned short  family;
        __sum16         (*checksum)(struct sk_buff *skb, unsigned int hook,
                                    unsigned int dataoff, u_int8_t protocol);
+       __sum16         (*checksum_partial)(struct sk_buff *skb,
+                                           unsigned int hook,
+                                           unsigned int dataoff,
+                                           unsigned int len,
+                                           u_int8_t protocol);
        int             (*route)(struct dst_entry **dst, struct flowi *fl);
        void            (*saveroute)(const struct sk_buff *skb,
                                     struct nf_queue_entry *entry);
@@ -263,6 +268,23 @@ nf_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff,
        return csum;
 }
 
+static inline __sum16
+nf_checksum_partial(struct sk_buff *skb, unsigned int hook,
+                   unsigned int dataoff, unsigned int len,
+                   u_int8_t protocol, unsigned short family)
+{
+       const struct nf_afinfo *afinfo;
+       __sum16 csum = 0;
+
+       rcu_read_lock();
+       afinfo = nf_get_afinfo(family);
+       if (afinfo)
+               csum = afinfo->checksum_partial(skb, hook, dataoff, len,
+                                               protocol);
+       rcu_read_unlock();
+       return csum;
+}
+
 extern int nf_register_afinfo(const struct nf_afinfo *afinfo);
 extern void nf_unregister_afinfo(const struct nf_afinfo *afinfo);