From fa13a8485ce07aecfbfa481baccfc33565f0be0d Mon Sep 17 00:00:00 2001 From: Rob Austein Date: Wed, 20 May 2015 16:57:33 -0400 Subject: Add csprng and hash modules. Add real error codes instead of magic numbers, and propegate error codes up from lower layers. Whack C++-isms, add parenthesese to a lot of macro expressions for evaluation safety, other minor cleanup. --- csprng.c | 93 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 93 insertions(+) create mode 100644 csprng.c (limited to 'csprng.c') diff --git a/csprng.c b/csprng.c new file mode 100644 index 0000000..f4f835d --- /dev/null +++ b/csprng.c @@ -0,0 +1,93 @@ +/* + * csprng.c + * ------------------------------ + * + * HAL interface to Cryptech CSPRNG/TRNG. + * + * Authors: Joachim Strömbergson, Paul Selkirk, Rob Austein + * Copyright (c) 2014-2015, SUNET + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include +#include +#include +#include + +#if 0 +#include +#include +#include +#include +#include +#include +#endif + +#include "cryptech.h" + +#ifndef WAIT_FOR_CSPRNG_VALID +#define WAIT_FOR_CSPRNG_VALID 1 +#endif + +hal_error_t hal_random(void *buffer, const size_t length) +{ + uint8_t temp[4], *buf = buffer; + hal_error_t err; + size_t i; + + for (i = 0; i < length; i += 4) { + const int last = (length - i) < 4; + + if (WAIT_FOR_CSPRNG_VALID && (err = hal_io_wait_valid(CSPRNG_ADDR_STATUS)) != HAL_OK) + return err; + + if ((err = hal_io_read(CSPRNG_ADDR_RANDOM, (last ? temp : &buf[i]), 4)) != HAL_OK) + return err; + + if (last) + for (; i < length; i++) + buf[i] = temp[i&3]; + } + + for (i = 0, buf = buffer; i < length; i++, buf++) + if (*buf != 0) + return HAL_OK; + + return HAL_ERROR_CSPRNG_ZEROED; +} + +/* + * "Any programmer who fails to comply with the standard naming, formatting, + * or commenting conventions should be shot. If it so happens that it is + * inconvenient to shoot him, then he is to be politely requested to recode + * his program in adherence to the above standard." + * -- Michael Spier, Digital Equipment Corporation + * + * Local variables: + * indent-tabs-mode: nil + * End: + */ -- cgit v1.2.3