diff options
-rw-r--r-- | bsp-howto/getentropy.rst | 5 | ||||
-rw-r--r-- | c-user/fatal_error.rst | 3 |
2 files changed, 6 insertions, 2 deletions
diff --git a/bsp-howto/getentropy.rst b/bsp-howto/getentropy.rst index b460450..10303a3 100644 --- a/bsp-howto/getentropy.rst +++ b/bsp-howto/getentropy.rst @@ -21,7 +21,10 @@ turn are used by various cryptographic functions. suitable for such applications. The :c:func:`getentropy` implementation must fill the specified memory region -of the given size with random numbers and return 0 on success. +of the given size with random numbers and return 0 on success. A non-zero +return may cause the :c:macro:`INTERNAL_ERROR_ARC4RANDOM_GETENTROPY_FAIL` +internal error by one of the +`ARC4RANDOM(3) <https://man.openbsd.org/arc4random.3>`_ functions. In general, for embedded systems it is not easy to get some real entropy. Normally, that can only be reached with some extra hardware support. Some microcontrollers diff --git a/c-user/fatal_error.rst b/c-user/fatal_error.rst index 396cb44..320227b 100644 --- a/c-user/fatal_error.rst +++ b/c-user/fatal_error.rst @@ -390,7 +390,8 @@ INTERNAL_ERROR_ILLEGAL_USE_OF_FLOATING_POINT_UNIT (38) INTERNAL_ERROR_ARC4RANDOM_GETENTROPY_FAIL (39) A :c:func:`getentropy` system call failed in one of the `ARC4RANDOM(3) - <https://man.openbsd.org/arc4random.3>`_ functions. + <https://man.openbsd.org/arc4random.3>`_ functions. This fatal error can + only be fixed with a different implementation of :c:func:`getentropy`. Operations ========== |