4 * \brief Random number generator (RNG) module documentation file.
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9 * SPDX-License-Identifier: Apache-2.0
11 * Licensed under the Apache License, Version 2.0 (the "License"); you may
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15 * http://www.apache.org/licenses/LICENSE-2.0
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23 * This file is part of mbed TLS (https://tls.mbed.org)
27 * @addtogroup rng_module Random number generator (RNG) module
29 * The Random number generator (RNG) module provides random number
30 * generation, see \c mbedtls_ctr_drbg_random().
32 * The block-cipher counter-mode based deterministic random
33 * bit generator (CTR_DBRG) as specified in NIST SP800-90. It needs an external
34 * source of entropy. For these purposes \c mbedtls_entropy_func() can be used.
35 * This is an implementation based on a simple entropy accumulator design.
37 * The other number generator that is included is less strong and uses the
38 * HAVEGE (HArdware Volatile Entropy Gathering and Expansion) software heuristic
39 * which considered unsafe for primary usage, but provides additional random
40 * to the entropy pool if enables.
42 * Meaning that there seems to be no practical algorithm that can guess
43 * the next bit with a probability larger than 1/2 in an output sequence.
45 * This module can be used to generate random numbers.