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/**
* @file
* Random number generator (RNG) module documentation file.
*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
/**
* @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.
*/