--- ./tcp_raw.c.orig 2001-03-15 09:33:04.000000000 +0100 +++ ./tcp_raw.c 2014-07-22 13:20:14.000000000 +0200 @@ -119,7 +119,7 @@ } struct iovec * -tcp_raw_input(struct libnet_ip_hdr *ip, struct libnet_tcp_hdr *tcp, int len) +tcp_raw_input(struct libnet_ipv4_hdr *ip, struct libnet_tcp_hdr *tcp, int len) { struct tha tha; struct tcp_conn *conn; @@ -131,7 +131,7 @@ /* Verify TCP checksum. */ cksum = tcp->th_sum; - libnet_do_checksum((u_char *) ip, IPPROTO_TCP, len); + libnet_do_checksum(NULL, (u_char *) ip, IPPROTO_TCP, len); if (cksum != tcp->th_sum) return (NULL);