How to normalize a DN as in entries?

[Hallvard B Furuseth <h.b.furuseth@usit.uio.no>]

How do I convert a DN which was input by the user to the format used in
Entry->e_nname?  There are several normalization routines in dn.c, I
don't know which one to use.

I'm updating my old patch
    http://folk.uio.no/hbf/OpenLDAP/slapcat-s.txt
to HEAD, and it needs check if a DN in the database is in the subtree
starting at the user-input DN.

-- 
Hallvard