doc_rng.h

00001 /**
00002  * @file
00003  * Random number generator (RNG) module documentation file.
00004  *
00005  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
00006  *  SPDX-License-Identifier: Apache-2.0
00007  *
00008  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
00009  *  not use this file except in compliance with the License.
00010  *  You may obtain a copy of the License at
00011  *
00012  *  http://www.apache.org/licenses/LICENSE-2.0
00013  *
00014  *  Unless required by applicable law or agreed to in writing, software
00015  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00016  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00017  *  See the License for the specific language governing permissions and
00018  *  limitations under the License.
00019  *
00020  *  This file is part of mbed TLS (https://tls.mbed.org)
00021  */
00022 
00023 /**
00024  * @addtogroup rng_module Random number generator (RNG) module
00025  *
00026  * The Random number generator (RNG) module provides random number
00027  * generation, see \c mbedtls_ctr_drbg_random().
00028  *
00029  * The block-cipher counter-mode based deterministic random
00030  * bit generator (CTR_DBRG) as specified in NIST SP800-90. It needs an external
00031  * source of entropy. For these purposes \c mbedtls_entropy_func() can be used.
00032  * This is an implementation based on a simple entropy accumulator design.
00033  *
00034  * The other number generator that is included is less strong and uses the
00035  * HAVEGE (HArdware Volatile Entropy Gathering and Expansion) software heuristic
00036  * which considered unsafe for primary usage, but provides additional random
00037  * to the entropy pool if enables.
00038  *
00039  * Meaning that there seems to be no practical algorithm that can guess
00040  * the next bit with a probability larger than 1/2 in an output sequence.
00041  *
00042  * This module can be used to generate random numbers.
00043  */