On Fri, May 17, 2013 at 3:35 PM, Oliver SchinaglWhile that is a great idea, we can't guarantee device uniqueness. We've already seen some chips that where 'forgotten' to program and default set to all 0. I guess that doesn't have to be a bad thing.
<oliver+list@xxxxxxxxxxx> wrote:
(...)While initially these fuses are used to somewhat determin the chipID, these(...)
appear to be writeable by the user and thus can be used for other purpouses.
For example storing a 128 bit root key, a unique serial number, which could
then even be used as a MAC address.
Then follows some code to read out the keys from sysfs I guess..
+static int __init sid_probe(struct platform_device *pdev)
It's really simple to actually make the kernel use this to seed the
entropy pool.
#include <linux/random.h>
add_device_randomness(u8 *, num);
If you know after probe that you can read out a number of bytes
of device-unique data, I think you should add those bytes to the
entropy pool like this.
Yours,
Linus Walleij