Matching rule against IP subnet

[manu@netbsd.org (Emmanuel Dreyfus)]

Hello

As far as I know, it is not possible to match an IP subnet. For
instance, if I have an object like this:

dn: cn=foo,o=example
managedAddr: 192.0.2.0/24

And this kind of thing does not seems available:
ldapsearch 'managedAddr:addressInSubnetMatch:=192.0.2.1'

I can think of a few useful matching rules:
addressInSubnetMatch
subnetInSubnetMatch
subnetContainsSubnetMatch
subnetContainsAddressMatch
subnetExactMatch        (192.0.2.5/24 and 192.0.2.10/24 are the same)

Questions:
- can someone confirm this cannot be done yet?
- is there a RFC to implement that does this? Or should I start with
what I have though about and presented above?
- is this functionnality welcome?
- where do I start to implement it? The thing happen in schema_init.c
and schema_prep.c, but I need to select an OID. How?

The motivation is DNS configuration stored in LDAP. That feature could
enable the delegation of subnet management to different administrators,
the access being enforced by slapd ACL.

-- 
Emmanuel Dreyfus
http://hcpnet.free.fr/pubz
manu@netbsd.org