PFTM_FRAG
pt.timeout = PFTM_FRAG;
pf->timeout[PFTM_FRAG] = PFTM_FRAG_VAL;
{ "frag", PFTM_FRAG },
timeout[PFTM_FRAG] = PFTM_FRAG_VAL;
expire = getuptime() - pf_default_rule.timeout[PFTM_FRAG];
stale = pf_default_rule.timeout[PFTM_FRAG] * PF_FRAG_STALE;