tighten variable length header parsing. XXX overwriting sadb_extlen is a bad idea, i believe.
tighten variable length header parsing.
XXX overwriting sadb_extlen is a bad idea, i believe.

MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame