WPA Supplicant license

[Fariya]

Hi,

I am planning to add up some proprietary features as a part of the WPA 
Supplicant. My question here is pertaining to the license. I know that 
the WPA Supplicant has BSD license and that I can use it. But I need a 
little clarification here: If I choose to use BSD license does it mean 
that the source code for my proprietary work (added on the supplicant) 
need not be made freely avilable?

Regards,
Fariya