DHCP and Option 82

[Alan DeKok]

On Feb 19, 2018, at 11:18 AM, Daniel Ryšlink <ryslink at dialtelecom.cz> wrote:
> Can anyone please provide a link to a working example of a Freeradius with DHCP virtual server where the users accessing the network are identified not by a MAC address, nor by Calling-Station-ID, but by the attributes encoded into Option 82, specifically in the radius packet:
> 
> (0)   ADSL-Agent-Circuit-Id = 0x4769302f31393a3130
> (0)   ADSL-Agent-Remote-Id = 0x010b465454582d535749544348

  Yeah... those are horribly formatted.  And not automatically decoded by the server.

> I use MySQL as a backend for my ippools, but the queries.conf work only operate with "Calling-Station-Id", or "Nas-Port-Id".

  That's because it's designed to work with RADIUS packets.

  You can also see raddb/mods-config/ippool-dhcp/ which contains examples of IP pools for DHCP.

  The module configuration is in raddb/mods-available/dhcp_sqlippool

> Is the solution to define in mods-enabled/dhcp something like:
> 
> dhcp {
>         Calling-Station-Id = %{dhcp_options:<Circuit-ID>}%{dhcp_options:<Agent-ID>}
> }

  You can't just create things in the configuration and expect them to do what you want.  The configuration items are documented: what they are, and how they work.

  Read raddb/sites-available/dhcp.  It contains a sample virtual server for DHCP.  It also references the "dhcp_sqlippool" module described above.

  You can edit those files to do IP pool assignment for DHCP, using the relay options.

  Alan DeKok.