This is why I use, in security critical contents of my software (where the numbers have to be computationally infeasible to produce), a type of random number generator called an XOF (extendable-output function).
It takes entropy from multiple different sources, makes it all input to the XOF, then the XOF uses cryptography to output a stream that has as much entropy as the combined entropy of all of its sources of randomness. So if an XOF, for example, takes 100 runs of rdrand16, along with the system time in microseconds and the number of milliseconds between receiving 100 packets over the network, the XOF will output a completely random stream without artifacts like never returning 0x0000, even if rdrand16 never outputs 0x0000.
Well that very similar to how the Linux kernel does it. The linux kernel does it a little differently in that it uses the chacha8 stream cipher instead of a XOF. The chacha8 stream key is frequently reseeded by hashing the entropy pool with blake2b over the collected randomness from all sources but a lot comes from the nanosecond timing of hardware interrupts. Depending on configuration the blocking rng does not return unless 256 bits of trusted randomness are mixed into the entropy pool.
If anyone is interested in this topic please just read the code[0]. It has a lot of interesting tricks that you would not have just rolling your own.
strenholme · · focus · HN ↗
It takes entropy from multiple different sources, makes it all input to the XOF, then the XOF uses cryptography to output a stream that has as much entropy as the combined entropy of all of its sources of randomness. So if an XOF, for example, takes 100 runs of rdrand16, along with the system time in microseconds and the number of milliseconds between receiving 100 packets over the network, the XOF will output a completely random stream without artifacts like never returning 0x0000, even if rdrand16 never outputs 0x0000.
ironhaven · · focus · HN ↗
If anyone is interested in this topic please just read the code[0]. It has a lot of interesting tricks that you would not have just rolling your own.
[0]<a href="https://github.com/torvalds/linux/blob/master/drivers/char/random.c" rel="nofollow">https://github.com/torvalds/linux/blob/master/drivers/char/r...