Safetrust IoT sensor

Random Number Generation is performed by the PRNG_Fortuna, which implements the following features:
- It uses 32 independent entropy pools, each filling at different rates and feeding reseeds at controlled intervals.
- Reseed mechanism: when enough entropy has accumulated, choose which pools to concatenate entropy based on the reseed counter. Hashes the output with the current generator key to produce a new generator key.
- Forward security: new key derived from fresh entropy after each reseed, old key discarded.
- Backward security: 32 pools with exponential delay; attacker needs entropy from very old, rare pools.