random.random() is not based on /dev/urandom

[oplik0]

The README states: Note: Cracker does not implement prediction of random() function since it is based on the os.urandom module which is based on /dev/urandom - however, at least in current versions of CPython, this is not true. You can find the implementation of this function for Python 3.10 here: https://github.com/python/cpython/blob/60adc4b92a8a6fe115a023c8f639a6de4730fac1/Modules/_randommodule.c#L153-L177
It's basically these two lines:

uint32_t a=genrand_uint32(self)>>5, b=genrand_uint32(self)>>6;
return PyFloat_FromDouble((a*67108864.0+b)*(1.0/9007199254740992.0));

with genrand_uint32 being the MT random generator, the same as in getrandbits(). One needs to use SystemRandom to get the randomness from the os directly.

There is a slight loss of information about the state here, as in total 11 bits are zeroed, so I'm not sure if it can be used to crack the generator anyway, but it might be a good idea to correct the README at least, and I'll try to add a prediction generator at least.