doc_rng.h 1.7 KB

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  1. /**
  2. * @file
  3. * Random number generator (RNG) module documentation file.
  4. *
  5. * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
  6. * SPDX-License-Identifier: Apache-2.0
  7. *
  8. * Licensed under the Apache License, Version 2.0 (the "License"); you may
  9. * not use this file except in compliance with the License.
  10. * You may obtain a copy of the License at
  11. *
  12. * http://www.apache.org/licenses/LICENSE-2.0
  13. *
  14. * Unless required by applicable law or agreed to in writing, software
  15. * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  16. * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  17. * See the License for the specific language governing permissions and
  18. * limitations under the License.
  19. *
  20. * This file is part of mbed TLS (https://tls.mbed.org)
  21. */
  22. /**
  23. * @addtogroup rng_module Random number generator (RNG) module
  24. *
  25. * The Random number generator (RNG) module provides random number
  26. * generation, see \c mbedtls_ctr_drbg_random().
  27. *
  28. * The block-cipher counter-mode based deterministic random
  29. * bit generator (CTR_DBRG) as specified in NIST SP800-90. It needs an external
  30. * source of entropy. For these purposes \c mbedtls_entropy_func() can be used.
  31. * This is an implementation based on a simple entropy accumulator design.
  32. *
  33. * The other number generator that is included is less strong and uses the
  34. * HAVEGE (HArdware Volatile Entropy Gathering and Expansion) software heuristic
  35. * which considered unsafe for primary usage, but provides additional random
  36. * to the entropy pool if enables.
  37. *
  38. * Meaning that there seems to be no practical algorithm that can guess
  39. * the next bit with a probability larger than 1/2 in an output sequence.
  40. *
  41. * This module can be used to generate random numbers.
  42. */