eth_compose(b, flow->dl_dst, flow->dl_src, ntohs(flow->dl_type), 0);
if (flow->dl_type == htons(FLOW_DL_TYPE_NONE)) {
struct eth_header *eth = b->l2;
eth_compose(b, flow->dl_dst, flow->dl_src, ntohs(flow->dl_type), 0);
if (flow->dl_type == htons(FLOW_DL_TYPE_NONE)) {
struct eth_header *eth = b->l2;