refactoring idmap code in smbd

[Esh, Andrew]

>On Wed, 9 Jul 2003, Esh, Andrew wrote:

>> Right now, windbindd simply has a range of IDs it can assign, which is
>> configurable. ... Such a range may not always be enough, ...

>Given a 32 bit uid space, have you come across this being 
>a problem in practice?

We have an application which requires IDs be the same across multiple
servers. A hash function was used to assign UIDs within the winbind range in
order to avoid having to synchronize ID assignments across servers. The hash
function was only reasonably collision free when large ranges were assigned
to winbindd, or when trusted domains were disallowed.

>Write your own IDmap backend and implement idmap_allocate_id() 
>however you want.  Very flexible. :-)

I'll look into that. We've already solved some other distribution problems
like this with a postgres database. Perhaps our idmap backend can be written
to use that.