ddpehdr
struct ddpehdr *deh = NULL, ddpe;
if (m->m_len < sizeof(struct ddpehdr) &&
((m = m_pullup(m, sizeof(struct ddpehdr))) == 0)) {
deh = mtod(m, struct ddpehdr *);
memcpy((void *) & ddpe, (void *) deh, sizeof(struct ddpehdr));
m_adj(m, sizeof(struct ddpehdr));
struct ddpehdr *deh;
M_PREPEND(m, sizeof(struct ddpehdr), M_DONTWAIT);
deh = mtod(m, struct ddpehdr *);