[CentOS] [OT] DHCP auth&auth software

Sun Oct 18 13:58:36 UTC 2009
Marko Vojinovic <vvmarko at gmail.com>

Does anyone know about some free (as in beer, and maybe as in speech) software 
which would implement authentication and authorization of a user prior to 
issuing a valid dhcp lease?

I imagine the following scenario: someone walks into my office building with a 
laptop (a colleague, a visitor, a guest, whoever), and hooks up onto the local 
net (wired or wireless). The server detects an unknown MAC address, issues a 
bogus dhcp lease which resolves all dns queries to a single internal web page 
with a form the user is supposed to fill in and send. After he does so, an 
administrator does a sanity check of the data the user provided, and grants or 
denies access. If access is granted, the user gets a new, unrestricted dhcp 
lease, which provides him with a normal access to local network.

The goal is to have a database which relates IP or MAC addresses to people 
names, so I can track a person down efficiently if he brings an 
infected/spamming machine into the building.

I would know how to build this infrastructure manually, but it's a lot of 
work, and I don't want to reinvent the wheel. Google somehow failed to help, 
or I failed to provide the right keywords. :-(

So what are my options?

TIA, :-)
Marko