extern int icmp_rcv(struct sk_buff *skb);
extern int icmp_ioctl(struct sock *sk, int cmd, unsigned long arg);
extern void icmp_init(struct net_proto_family *ops);
extern int icmp_rcv(struct sk_buff *skb);
extern int icmp_ioctl(struct sock *sk, int cmd, unsigned long arg);
extern void icmp_init(struct net_proto_family *ops);