libtests/getentropy01/init.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /*
0004  * Copyright (c) 2017 embedded brains GmbH & Co. KG
0005  *
0006  * Redistribution and use in source and binary forms, with or without
0007  * modification, are permitted provided that the following conditions
0008  * are met:
0009  * 1. Redistributions of source code must retain the above copyright
0010  *    notice, this list of conditions and the following disclaimer.
0011  * 2. Redistributions in binary form must reproduce the above copyright
0012  *    notice, this list of conditions and the following disclaimer in the
0013  *    documentation and/or other materials provided with the distribution.
0014  *
0015  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0016  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0017  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0018  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0019  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0020  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0021  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0022  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0023  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0024  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0025  * POSSIBILITY OF SUCH DAMAGE.
0026  */
0027
0028 #ifdef HAVE_CONFIG_H
0029 #include "config.h"
0030 #endif
0031
0032 #include "tmacros.h"
0033
0034 #include <rtems.h>
0035 #include <unistd.h>
0036 #include <assert.h>
0037
0038 const char rtems_test_name[] = "GETENTROPY 1";
0039
0040 #define TEST_MAX_BYTES 32
0041 #define TEST_GUARD_BYTES 32
0042 #define TEST_GUARD 0xA5
0043
0044 static char entropy_buffer1 [TEST_MAX_BYTES + TEST_GUARD_BYTES];
0045 static char entropy_buffer2 [TEST_MAX_BYTES + TEST_GUARD_BYTES];
0046 static char guard_buffer [TEST_MAX_BYTES + TEST_GUARD_BYTES];
0047
0048 static void test_getentropy(size_t nr_bytes)
0049 {
0050   int rv;
0051   size_t try = 1;
0052
0053   /*
0054    * For very small patterns, the probability that two random patterns are the
0055    * same is quite high. Therefore retry the test for these a few times.
0056    */
0057   if (nr_bytes < 4) {
0058     try = 4;
0059   }
0060
0061   do {
0062     --try;
0063
0064     /* Fill buffers with guard pattern */
0065     memset(entropy_buffer1, TEST_GUARD, sizeof(entropy_buffer1));
0066     memset(entropy_buffer2, TEST_GUARD, sizeof(entropy_buffer2));
0067     memset(guard_buffer, TEST_GUARD, sizeof(entropy_buffer2));
0068
0069     /* Get entropy with the given size */
0070     rv = getentropy(entropy_buffer1, nr_bytes);
0071     assert(rv == 0);
0072     rv = getentropy(entropy_buffer2, nr_bytes);
0073     assert(rv == 0);
0074
0075     /* Check guard pattern */
0076     rv = memcmp(entropy_buffer1 + nr_bytes, guard_buffer + nr_bytes,
0077         sizeof(entropy_buffer1) - nr_bytes);
0078     assert(rv == 0);
0079     rv = memcmp(entropy_buffer2 + nr_bytes, guard_buffer + nr_bytes,
0080         sizeof(entropy_buffer2) - nr_bytes);
0081     assert(rv == 0);
0082
0083     /* Make sure that buffers are not the same */
0084     rv = memcmp(entropy_buffer1, entropy_buffer2, sizeof(entropy_buffer1));
0085   } while (try > 0 && rv == 0);
0086   assert(rv != 0);
0087 }
0088
0089 static void Init(rtems_task_argument arg)
0090 {
0091   size_t i;
0092
0093   TEST_BEGIN();
0094
0095   for (i = 1; i <= TEST_MAX_BYTES; ++i) {
0096     test_getentropy(i);
0097   }
0098
0099   TEST_END();
0100
0101   rtems_test_exit(0);
0102 }
0103
0104 #define CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER
0105 #define CONFIGURE_APPLICATION_NEEDS_SIMPLE_CONSOLE_DRIVER
0106
0107 #define CONFIGURE_MAXIMUM_TASKS 1
0108
0109 #define CONFIGURE_INITIAL_EXTENSIONS RTEMS_TEST_INITIAL_EXTENSION
0110
0111 #define CONFIGURE_RTEMS_INIT_TASKS_TABLE
0112
0113 #define CONFIGURE_INIT
0114
0115 #include <rtems/confdefs.h>