The Random number generator (RNG) module provides random number generation, see mbedtls_ctr_drbg_random().

The block-cipher counter-mode based deterministic random bit generator (CTR_DBRG) as specified in NIST SP800-90. It needs an external source of entropy. For these purposes mbedtls_entropy_func() can be used. This is an implementation based on a simple entropy accumulator design.

Meaning that there seems to be no practical algorithm that can guess the next bit with a probability larger than 1/2 in an output sequence.

This module can be used to generate random numbers.