frdm k64f ethernet support

Hi, according to: The ethernet driver for the frdm k64f is WIP. I'm interested on this, is there a repository where I can see/contribute to the current work? If not, I've seen there is an LWIP port of this board (baremetal) in the Kinetis SDK. It includes ethernet drivers with BSD License. If I adapt those drivers to be used in RIOT, will i be able to contribute it besides the license? Do you think it is convenient to use those drivers?. Thanks for answering!