Is this possible?

Hi!

I have a driver that encrypts all data from the hard disk, including the partition where Windows is installed.
At boot time, I get my key and algorithm from a USB Stick to be able to boot Windows.

Now the question. Is it possible to get this key and algoritms from the network. Is it possible to make a boot loader in ASM that does this?
If the answer is yes could you tell me in theory how this can be done?

Thanks!