text: /**
   * \file doc_rng.h
   *
   * \brief Random number generator (RNG) module documentation file.
   */
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  /**
   * @addtogroup rng_module Random number generator (RNG) module
   *
   * The Random number generator (RNG) module provides random number
   * generation, see \c 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 \c mbedtls_entropy_func() can be used.
   * This is an implementation based on a simple entropy accumulator design.
   *
   * The other number generator that is included is less strong and uses the
   * HAVEGE (HArdware Volatile Entropy Gathering and Expansion) software heuristic
   * which considered unsafe for primary usage, but provides additional random
   * to the entropy pool if enables.
   *
   * 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.
   */
  