blob: 5ca333a675adee4662ed38cfdadc856ce2bc75bb [file] [log] [blame]
/**
* \file random.c
*
* \brief This file contains the helper functions to generate random numbers
* for the purpose of testing.
*/
/*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* for arc4random_buf() from <stdlib.h>
*/
#if defined(__NetBSD__)
#define _NETBSD_SOURCE 1
#elif defined(__OpenBSD__)
#define _BSD_SOURCE 1
#endif
#include <test/macros.h>
#include <test/random.h>
#include <string.h>
#include <mbedtls/entropy.h>
#include "../../library/alignment.h"
int mbedtls_test_rnd_std_rand(void *rng_state,
unsigned char *output,
size_t len)
{
#if !defined(__OpenBSD__) && !defined(__NetBSD__)
size_t i;
if (rng_state != NULL) {
rng_state = NULL;
}
for (i = 0; i < len; ++i) {
output[i] = rand();
}
#else
if (rng_state != NULL) {
rng_state = NULL;
}
arc4random_buf(output, len);
#endif /* !OpenBSD && !NetBSD */
return 0;
}
int mbedtls_test_rnd_zero_rand(void *rng_state,
unsigned char *output,
size_t len)
{
if (rng_state != NULL) {
rng_state = NULL;
}
memset(output, 0, len);
return 0;
}
int mbedtls_test_rnd_buffer_rand(void *rng_state,
unsigned char *output,
size_t len)
{
mbedtls_test_rnd_buf_info *info = (mbedtls_test_rnd_buf_info *) rng_state;
size_t use_len;
if (rng_state == NULL) {
return mbedtls_test_rnd_std_rand(NULL, output, len);
}
use_len = len;
if (len > info->length) {
use_len = info->length;
}
if (use_len) {
memcpy(output, info->buf, use_len);
info->buf += use_len;
info->length -= use_len;
}
if (len - use_len > 0) {
if (info->fallback_f_rng != NULL) {
return info->fallback_f_rng(info->fallback_p_rng,
output + use_len,
len - use_len);
} else {
return MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
}
}
return 0;
}
int mbedtls_test_rnd_pseudo_rand(void *rng_state,
unsigned char *output,
size_t len)
{
mbedtls_test_rnd_pseudo_info *info =
(mbedtls_test_rnd_pseudo_info *) rng_state;
uint32_t i, *k, sum, delta = 0x9E3779B9;
unsigned char result[4], *out = output;
if (rng_state == NULL) {
return mbedtls_test_rnd_std_rand(NULL, output, len);
}
k = info->key;
while (len > 0) {
size_t use_len = (len > 4) ? 4 : len;
sum = 0;
for (i = 0; i < 32; i++) {
info->v0 += (((info->v1 << 4) ^ (info->v1 >> 5))
+ info->v1) ^ (sum + k[sum & 3]);
sum += delta;
info->v1 += (((info->v0 << 4) ^ (info->v0 >> 5))
+ info->v0) ^ (sum + k[(sum>>11) & 3]);
}
MBEDTLS_PUT_UINT32_BE(info->v0, result, 0);
memcpy(out, result, use_len);
len -= use_len;
out += 4;
}
return 0;
}