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Entropy use in embedded system


Jun 20, 2017 17:45
Larry Harmon

I want to use mbedTLS on a small, bare metal embedded system. I need to generate keys as well as using hashing functions.

How is entropy used in non-OS embedded systems?

The processor I'm using has a Pseudo random number generator, but it needs seeded with an 80 bit number.

What is the suggested model for non-OS embedded systems?

Thanks, Larry

 
Jun 21, 2017 13:23
Ron Eldor

Hi Larry,
As you probably know, the seed is collected by the True Random Number Generator (TRNG), which collects the entropy bits.
Since you are using a non-OS bare metal device, I suggest you check if your device has a HW entropy collector\TRNG, and integrate it to your product, as described here.
In addition, you can find the following two articles interesting:

I hope you can continue with these hints
Regards,
mbed TLS Team member
Ron