OVS_CS_F_SRC_NAT
#define OVS_CS_F_NAT_MASK (OVS_CS_F_SRC_NAT | OVS_CS_F_DST_NAT)
state |= OVS_CS_F_SRC_NAT;
key->ct_state |= OVS_CS_F_SRC_NAT;
OVS_CS_F_SRC_NAT | OVS_CS_F_DST_NAT)
key->ct_state &= ~OVS_CS_F_SRC_NAT;