static unsigned int hook_ipv4(HOOK_ARG_TYPE hook, struct sk_buff *skb, const struct net_device *in, const struct net_device *out, int (*okfn)(struct sk_buff *)) { return core_4to6(skb); }
static NF_CALLBACK(hook_ipv4, skb) { return core_4to6(skb, skb->dev); }