map_sip_addr 204 net/ipv4/netfilter/nf_nat_sip.c if (!map_sip_addr(skb, dptr, datalen, SIP_HDR_FROM) || map_sip_addr 205 net/ipv4/netfilter/nf_nat_sip.c !map_sip_addr(skb, dptr, datalen, SIP_HDR_TO))