nf_checksum 785 net/netfilter/nf_conntrack_proto_tcp.c nf_checksum(skb, hooknum, dataoff, IPPROTO_TCP, pf)) { nf_checksum 127 net/netfilter/nf_conntrack_proto_udp.c nf_checksum(skb, hooknum, dataoff, IPPROTO_UDP, pf)) {