proxmark3/common/mbedtls/entropy.c

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/*
* Entropy accumulator implementation
*
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* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0
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*
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* 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
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* 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.
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*/
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#include "common.h"
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#if defined(MBEDTLS_ENTROPY_C)
#if defined(MBEDTLS_TEST_NULL_ENTROPY)
#warning "**** WARNING! MBEDTLS_TEST_NULL_ENTROPY defined! "
#warning "**** THIS BUILD HAS NO DEFINED ENTROPY SOURCES "
#warning "**** THIS BUILD IS *NOT* SUITABLE FOR PRODUCTION USE "
#endif
#include "mbedtls/entropy.h"
#include "mbedtls/entropy_poll.h"
#include "mbedtls/platform_util.h"
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#include "mbedtls/error.h"
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#include <string.h>
#if defined(MBEDTLS_FS_IO)
#include <stdio.h>
#endif
#if defined(MBEDTLS_ENTROPY_NV_SEED)
#include "mbedtls/platform.h"
#endif
#if defined(MBEDTLS_SELF_TEST)
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdio.h>
#define mbedtls_printf printf
#endif /* MBEDTLS_PLATFORM_C */
#endif /* MBEDTLS_SELF_TEST */
#if defined(MBEDTLS_HAVEGE_C)
#include "mbedtls/havege.h"
#endif
#define ENTROPY_MAX_LOOP 256 /**< Maximum amount to loop before error */
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void mbedtls_entropy_init(mbedtls_entropy_context *ctx) {
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ctx->source_count = 0;
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memset(ctx->source, 0, sizeof(ctx->source));
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#if defined(MBEDTLS_THREADING_C)
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mbedtls_mutex_init(&ctx->mutex);
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#endif
ctx->accumulator_started = 0;
#if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
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mbedtls_sha512_init(&ctx->accumulator);
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#else
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mbedtls_sha256_init(&ctx->accumulator);
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#endif
#if defined(MBEDTLS_HAVEGE_C)
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mbedtls_havege_init(&ctx->havege_data);
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#endif
/* Reminder: Update ENTROPY_HAVE_STRONG in the test files
* when adding more strong entropy sources here. */
#if defined(MBEDTLS_TEST_NULL_ENTROPY)
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mbedtls_entropy_add_source(ctx, mbedtls_null_entropy_poll, NULL,
1, MBEDTLS_ENTROPY_SOURCE_STRONG);
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#endif
#if !defined(MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES)
#if !defined(MBEDTLS_NO_PLATFORM_ENTROPY)
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mbedtls_entropy_add_source(ctx, mbedtls_platform_entropy_poll, NULL,
MBEDTLS_ENTROPY_MIN_PLATFORM,
MBEDTLS_ENTROPY_SOURCE_STRONG);
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#endif
#if defined(MBEDTLS_TIMING_C)
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mbedtls_entropy_add_source(ctx, mbedtls_hardclock_poll, NULL,
MBEDTLS_ENTROPY_MIN_HARDCLOCK,
MBEDTLS_ENTROPY_SOURCE_WEAK);
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#endif
#if defined(MBEDTLS_HAVEGE_C)
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mbedtls_entropy_add_source(ctx, mbedtls_havege_poll, &ctx->havege_data,
MBEDTLS_ENTROPY_MIN_HAVEGE,
MBEDTLS_ENTROPY_SOURCE_STRONG);
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#endif
#if defined(MBEDTLS_ENTROPY_HARDWARE_ALT)
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mbedtls_entropy_add_source(ctx, mbedtls_hardware_poll, NULL,
MBEDTLS_ENTROPY_MIN_HARDWARE,
MBEDTLS_ENTROPY_SOURCE_STRONG);
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#endif
#if defined(MBEDTLS_ENTROPY_NV_SEED)
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mbedtls_entropy_add_source(ctx, mbedtls_nv_seed_poll, NULL,
MBEDTLS_ENTROPY_BLOCK_SIZE,
MBEDTLS_ENTROPY_SOURCE_STRONG);
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ctx->initial_entropy_run = 0;
#endif
#endif /* MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES */
}
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void mbedtls_entropy_free(mbedtls_entropy_context *ctx) {
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/* If the context was already free, don't call free() again.
* This is important for mutexes which don't allow double-free. */
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if (ctx->accumulator_started == -1)
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return;
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#if defined(MBEDTLS_HAVEGE_C)
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mbedtls_havege_free(&ctx->havege_data);
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#endif
#if defined(MBEDTLS_THREADING_C)
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mbedtls_mutex_free(&ctx->mutex);
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#endif
#if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
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mbedtls_sha512_free(&ctx->accumulator);
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#else
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mbedtls_sha256_free(&ctx->accumulator);
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#endif
#if defined(MBEDTLS_ENTROPY_NV_SEED)
ctx->initial_entropy_run = 0;
#endif
ctx->source_count = 0;
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mbedtls_platform_zeroize(ctx->source, sizeof(ctx->source));
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ctx->accumulator_started = -1;
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}
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int mbedtls_entropy_add_source(mbedtls_entropy_context *ctx,
mbedtls_entropy_f_source_ptr f_source, void *p_source,
size_t threshold, int strong) {
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int idx, ret = 0;
#if defined(MBEDTLS_THREADING_C)
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if ((ret = mbedtls_mutex_lock(&ctx->mutex)) != 0)
return (ret);
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#endif
idx = ctx->source_count;
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if (idx >= MBEDTLS_ENTROPY_MAX_SOURCES) {
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ret = MBEDTLS_ERR_ENTROPY_MAX_SOURCES;
goto exit;
}
ctx->source[idx].f_source = f_source;
ctx->source[idx].p_source = p_source;
ctx->source[idx].threshold = threshold;
ctx->source[idx].strong = strong;
ctx->source_count++;
exit:
#if defined(MBEDTLS_THREADING_C)
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if (mbedtls_mutex_unlock(&ctx->mutex) != 0)
return (MBEDTLS_ERR_THREADING_MUTEX_ERROR);
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#endif
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return (ret);
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}
/*
* Entropy accumulator update
*/
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static int entropy_update(mbedtls_entropy_context *ctx, unsigned char source_id,
const unsigned char *data, size_t len) {
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unsigned char header[2];
unsigned char tmp[MBEDTLS_ENTROPY_BLOCK_SIZE];
size_t use_len = len;
const unsigned char *p = data;
int ret = 0;
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if (use_len > MBEDTLS_ENTROPY_BLOCK_SIZE) {
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#if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
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if ((ret = mbedtls_sha512_ret(data, len, tmp, 0)) != 0)
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goto cleanup;
#else
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if ((ret = mbedtls_sha256_ret(data, len, tmp, 0)) != 0)
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goto cleanup;
#endif
p = tmp;
use_len = MBEDTLS_ENTROPY_BLOCK_SIZE;
}
header[0] = source_id;
header[1] = use_len & 0xFF;
/*
* Start the accumulator if this has not already happened. Note that
* it is sufficient to start the accumulator here only because all calls to
* gather entropy eventually execute this code.
*/
#if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
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if (ctx->accumulator_started == 0 &&
(ret = mbedtls_sha512_starts_ret(&ctx->accumulator, 0)) != 0)
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goto cleanup;
else
ctx->accumulator_started = 1;
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if ((ret = mbedtls_sha512_update_ret(&ctx->accumulator, header, 2)) != 0)
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goto cleanup;
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ret = mbedtls_sha512_update_ret(&ctx->accumulator, p, use_len);
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#else
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if (ctx->accumulator_started == 0 &&
(ret = mbedtls_sha256_starts_ret(&ctx->accumulator, 0)) != 0)
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goto cleanup;
else
ctx->accumulator_started = 1;
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if ((ret = mbedtls_sha256_update_ret(&ctx->accumulator, header, 2)) != 0)
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goto cleanup;
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ret = mbedtls_sha256_update_ret(&ctx->accumulator, p, use_len);
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#endif
cleanup:
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mbedtls_platform_zeroize(tmp, sizeof(tmp));
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return (ret);
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}
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int mbedtls_entropy_update_manual(mbedtls_entropy_context *ctx,
const unsigned char *data, size_t len) {
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int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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#if defined(MBEDTLS_THREADING_C)
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if ((ret = mbedtls_mutex_lock(&ctx->mutex)) != 0)
return (ret);
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#endif
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ret = entropy_update(ctx, MBEDTLS_ENTROPY_SOURCE_MANUAL, data, len);
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#if defined(MBEDTLS_THREADING_C)
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if (mbedtls_mutex_unlock(&ctx->mutex) != 0)
return (MBEDTLS_ERR_THREADING_MUTEX_ERROR);
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#endif
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return (ret);
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}
/*
* Run through the different sources to add entropy to our accumulator
*/
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static int entropy_gather_internal(mbedtls_entropy_context *ctx) {
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int ret = MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
int i;
int have_one_strong = 0;
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unsigned char buf[MBEDTLS_ENTROPY_MAX_GATHER];
size_t olen;
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if (ctx->source_count == 0)
return (MBEDTLS_ERR_ENTROPY_NO_SOURCES_DEFINED);
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/*
* Run through our entropy sources
*/
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for (i = 0; i < ctx->source_count; i++) {
if (ctx->source[i].strong == MBEDTLS_ENTROPY_SOURCE_STRONG)
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have_one_strong = 1;
olen = 0;
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if ((ret = ctx->source[i].f_source(ctx->source[i].p_source,
buf, MBEDTLS_ENTROPY_MAX_GATHER, &olen)) != 0) {
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goto cleanup;
}
/*
* Add if we actually gathered something
*/
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if (olen > 0) {
if ((ret = entropy_update(ctx, (unsigned char) i,
buf, olen)) != 0)
return (ret);
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ctx->source[i].size += olen;
}
}
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if (have_one_strong == 0)
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ret = MBEDTLS_ERR_ENTROPY_NO_STRONG_SOURCE;
cleanup:
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mbedtls_platform_zeroize(buf, sizeof(buf));
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return (ret);
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}
/*
* Thread-safe wrapper for entropy_gather_internal()
*/
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int mbedtls_entropy_gather(mbedtls_entropy_context *ctx) {
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int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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#if defined(MBEDTLS_THREADING_C)
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if ((ret = mbedtls_mutex_lock(&ctx->mutex)) != 0)
return (ret);
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#endif
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ret = entropy_gather_internal(ctx);
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#if defined(MBEDTLS_THREADING_C)
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if (mbedtls_mutex_unlock(&ctx->mutex) != 0)
return (MBEDTLS_ERR_THREADING_MUTEX_ERROR);
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#endif
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return (ret);
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}
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int mbedtls_entropy_func(void *data, unsigned char *output, size_t len) {
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int ret, count = 0, i, thresholds_reached;
size_t strong_size;
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mbedtls_entropy_context *ctx = (mbedtls_entropy_context *) data;
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
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if (len > MBEDTLS_ENTROPY_BLOCK_SIZE)
return (MBEDTLS_ERR_ENTROPY_SOURCE_FAILED);
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#if defined(MBEDTLS_ENTROPY_NV_SEED)
/* Update the NV entropy seed before generating any entropy for outside
* use.
*/
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if (ctx->initial_entropy_run == 0) {
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ctx->initial_entropy_run = 1;
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if ((ret = mbedtls_entropy_update_nv_seed(ctx)) != 0)
return (ret);
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}
#endif
#if defined(MBEDTLS_THREADING_C)
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if ((ret = mbedtls_mutex_lock(&ctx->mutex)) != 0)
return (ret);
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#endif
/*
* Always gather extra entropy before a call
*/
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do {
if (count++ > ENTROPY_MAX_LOOP) {
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ret = MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
goto exit;
}
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if ((ret = entropy_gather_internal(ctx)) != 0)
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goto exit;
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thresholds_reached = 1;
strong_size = 0;
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for (i = 0; i < ctx->source_count; i++) {
if (ctx->source[i].size < ctx->source[i].threshold)
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thresholds_reached = 0;
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if (ctx->source[i].strong == MBEDTLS_ENTROPY_SOURCE_STRONG)
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strong_size += ctx->source[i].size;
}
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} while (! thresholds_reached || strong_size < MBEDTLS_ENTROPY_BLOCK_SIZE);
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memset(buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE);
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#if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
/*
* Note that at this stage it is assumed that the accumulator was started
* in a previous call to entropy_update(). If this is not guaranteed, the
* code below will fail.
*/
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if ((ret = mbedtls_sha512_finish_ret(&ctx->accumulator, buf)) != 0)
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goto exit;
/*
* Reset accumulator and counters and recycle existing entropy
*/
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mbedtls_sha512_free(&ctx->accumulator);
mbedtls_sha512_init(&ctx->accumulator);
if ((ret = mbedtls_sha512_starts_ret(&ctx->accumulator, 0)) != 0)
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goto exit;
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if ((ret = mbedtls_sha512_update_ret(&ctx->accumulator, buf,
MBEDTLS_ENTROPY_BLOCK_SIZE)) != 0)
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goto exit;
/*
* Perform second SHA-512 on entropy
*/
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if ((ret = mbedtls_sha512_ret(buf, MBEDTLS_ENTROPY_BLOCK_SIZE,
buf, 0)) != 0)
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goto exit;
#else /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */
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if ((ret = mbedtls_sha256_finish_ret(&ctx->accumulator, buf)) != 0)
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goto exit;
/*
* Reset accumulator and counters and recycle existing entropy
*/
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mbedtls_sha256_free(&ctx->accumulator);
mbedtls_sha256_init(&ctx->accumulator);
if ((ret = mbedtls_sha256_starts_ret(&ctx->accumulator, 0)) != 0)
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goto exit;
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if ((ret = mbedtls_sha256_update_ret(&ctx->accumulator, buf,
MBEDTLS_ENTROPY_BLOCK_SIZE)) != 0)
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goto exit;
/*
* Perform second SHA-256 on entropy
*/
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if ((ret = mbedtls_sha256_ret(buf, MBEDTLS_ENTROPY_BLOCK_SIZE,
buf, 0)) != 0)
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goto exit;
#endif /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */
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for (i = 0; i < ctx->source_count; i++)
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ctx->source[i].size = 0;
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memcpy(output, buf, len);
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ret = 0;
exit:
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mbedtls_platform_zeroize(buf, sizeof(buf));
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#if defined(MBEDTLS_THREADING_C)
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if (mbedtls_mutex_unlock(&ctx->mutex) != 0)
return (MBEDTLS_ERR_THREADING_MUTEX_ERROR);
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#endif
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return (ret);
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}
#if defined(MBEDTLS_ENTROPY_NV_SEED)
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int mbedtls_entropy_update_nv_seed(mbedtls_entropy_context *ctx) {
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int ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
/* Read new seed and write it to NV */
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if ((ret = mbedtls_entropy_func(ctx, buf, MBEDTLS_ENTROPY_BLOCK_SIZE)) != 0)
return (ret);
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if (mbedtls_nv_seed_write(buf, MBEDTLS_ENTROPY_BLOCK_SIZE) < 0)
return (MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR);
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/* Manually update the remaining stream with a separator value to diverge */
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memset(buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE);
ret = mbedtls_entropy_update_manual(ctx, buf, MBEDTLS_ENTROPY_BLOCK_SIZE);
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return (ret);
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}
#endif /* MBEDTLS_ENTROPY_NV_SEED */
#if defined(MBEDTLS_FS_IO)
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int mbedtls_entropy_write_seed_file(mbedtls_entropy_context *ctx, const char *path) {
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int ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
FILE *f;
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
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if ((f = fopen(path, "wb")) == NULL)
return (MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR);
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if ((ret = mbedtls_entropy_func(ctx, buf, MBEDTLS_ENTROPY_BLOCK_SIZE)) != 0)
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goto exit;
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if (fwrite(buf, 1, MBEDTLS_ENTROPY_BLOCK_SIZE, f) != MBEDTLS_ENTROPY_BLOCK_SIZE) {
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ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
goto exit;
}
ret = 0;
exit:
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mbedtls_platform_zeroize(buf, sizeof(buf));
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fclose(f);
return (ret);
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}
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int mbedtls_entropy_update_seed_file(mbedtls_entropy_context *ctx, const char *path) {
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int ret = 0;
FILE *f;
size_t n;
unsigned char buf[ MBEDTLS_ENTROPY_MAX_SEED_SIZE ];
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if ((f = fopen(path, "rb")) == NULL)
return (MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR);
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fseek(f, 0, SEEK_END);
n = (size_t) ftell(f);
fseek(f, 0, SEEK_SET);
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if (n > MBEDTLS_ENTROPY_MAX_SEED_SIZE)
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n = MBEDTLS_ENTROPY_MAX_SEED_SIZE;
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if (fread(buf, 1, n, f) != n)
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ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
else
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ret = mbedtls_entropy_update_manual(ctx, buf, n);
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fclose(f);
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mbedtls_platform_zeroize(buf, sizeof(buf));
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if (ret != 0)
return (ret);
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return (mbedtls_entropy_write_seed_file(ctx, path));
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}
#endif /* MBEDTLS_FS_IO */
#if defined(MBEDTLS_SELF_TEST)
#if !defined(MBEDTLS_TEST_NULL_ENTROPY)
/*
* Dummy source function
*/
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static int entropy_dummy_source(void *data, unsigned char *output,
size_t len, size_t *olen) {
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((void) data);
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memset(output, 0x2a, len);
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*olen = len;
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return (0);
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}
#endif /* !MBEDTLS_TEST_NULL_ENTROPY */
#if defined(MBEDTLS_ENTROPY_HARDWARE_ALT)
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static int mbedtls_entropy_source_self_test_gather(unsigned char *buf, size_t buf_len) {
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int ret = 0;
size_t entropy_len = 0;
size_t olen = 0;
size_t attempts = buf_len;
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while (attempts > 0 && entropy_len < buf_len) {
if ((ret = mbedtls_hardware_poll(NULL, buf + entropy_len,
buf_len - entropy_len, &olen)) != 0)
return (ret);
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entropy_len += olen;
attempts--;
}
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if (entropy_len < buf_len) {
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ret = 1;
}
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return (ret);
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}
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static int mbedtls_entropy_source_self_test_check_bits(const unsigned char *buf,
size_t buf_len) {
unsigned char set = 0xFF;
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unsigned char unset = 0x00;
size_t i;
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for (i = 0; i < buf_len; i++) {
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set &= buf[i];
unset |= buf[i];
}
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return (set == 0xFF || unset == 0x00);
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}
/*
* A test to ensure hat the entropy sources are functioning correctly
* and there is no obvious failure. The test performs the following checks:
* - The entropy source is not providing only 0s (all bits unset) or 1s (all
* bits set).
* - The entropy source is not providing values in a pattern. Because the
* hardware could be providing data in an arbitrary length, this check polls
* the hardware entropy source twice and compares the result to ensure they
* are not equal.
* - The error code returned by the entropy source is not an error.
*/
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int mbedtls_entropy_source_self_test(int verbose) {
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int ret = 0;
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unsigned char buf0[2 * sizeof(unsigned long long int)];
unsigned char buf1[2 * sizeof(unsigned long long int)];
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if (verbose != 0)
mbedtls_printf(" ENTROPY_BIAS test: ");
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memset(buf0, 0x00, sizeof(buf0));
memset(buf1, 0x00, sizeof(buf1));
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if ((ret = mbedtls_entropy_source_self_test_gather(buf0, sizeof(buf0))) != 0)
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goto cleanup;
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if ((ret = mbedtls_entropy_source_self_test_gather(buf1, sizeof(buf1))) != 0)
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goto cleanup;
/* Make sure that the returned values are not all 0 or 1 */
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if ((ret = mbedtls_entropy_source_self_test_check_bits(buf0, sizeof(buf0))) != 0)
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goto cleanup;
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if ((ret = mbedtls_entropy_source_self_test_check_bits(buf1, sizeof(buf1))) != 0)
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goto cleanup;
/* Make sure that the entropy source is not returning values in a
* pattern */
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ret = memcmp(buf0, buf1, sizeof(buf0)) == 0;
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cleanup:
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if (verbose != 0) {
if (ret != 0)
mbedtls_printf("failed\n");
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else
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mbedtls_printf("passed\n");
2018-11-08 00:05:02 +08:00
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mbedtls_printf("\n");
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}
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return (ret != 0);
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}
#endif /* MBEDTLS_ENTROPY_HARDWARE_ALT */
/*
* The actual entropy quality is hard to test, but we can at least
* test that the functions don't cause errors and write the correct
* amount of data to buffers.
*/
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int mbedtls_entropy_self_test(int verbose) {
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int ret = 1;
#if !defined(MBEDTLS_TEST_NULL_ENTROPY)
mbedtls_entropy_context ctx;
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE] = { 0 };
unsigned char acc[MBEDTLS_ENTROPY_BLOCK_SIZE] = { 0 };
size_t i, j;
#endif /* !MBEDTLS_TEST_NULL_ENTROPY */
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if (verbose != 0)
mbedtls_printf(" ENTROPY test: ");
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#if !defined(MBEDTLS_TEST_NULL_ENTROPY)
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mbedtls_entropy_init(&ctx);
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/* First do a gather to make sure we have default sources */
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if ((ret = mbedtls_entropy_gather(&ctx)) != 0)
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goto cleanup;
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ret = mbedtls_entropy_add_source(&ctx, entropy_dummy_source, NULL, 16,
MBEDTLS_ENTROPY_SOURCE_WEAK);
if (ret != 0)
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goto cleanup;
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if ((ret = mbedtls_entropy_update_manual(&ctx, buf, sizeof buf)) != 0)
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goto cleanup;
/*
* To test that mbedtls_entropy_func writes correct number of bytes:
* - use the whole buffer and rely on ASan to detect overruns
* - collect entropy 8 times and OR the result in an accumulator:
* any byte should then be 0 with probably 2^(-64), so requiring
* each of the 32 or 64 bytes to be non-zero has a false failure rate
* of at most 2^(-58) which is acceptable.
*/
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for (i = 0; i < 8; i++) {
if ((ret = mbedtls_entropy_func(&ctx, buf, sizeof(buf))) != 0)
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goto cleanup;
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for (j = 0; j < sizeof(buf); j++)
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acc[j] |= buf[j];
}
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for (j = 0; j < sizeof(buf); j++) {
if (acc[j] == 0) {
2018-11-08 00:05:02 +08:00
ret = 1;
goto cleanup;
}
}
#if defined(MBEDTLS_ENTROPY_HARDWARE_ALT)
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if ((ret = mbedtls_entropy_source_self_test(0)) != 0)
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goto cleanup;
#endif
cleanup:
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mbedtls_entropy_free(&ctx);
2018-11-08 00:05:02 +08:00
#endif /* !MBEDTLS_TEST_NULL_ENTROPY */
2021-05-14 17:00:46 +08:00
if (verbose != 0) {
if (ret != 0)
mbedtls_printf("failed\n");
2018-11-08 00:05:02 +08:00
else
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mbedtls_printf("passed\n");
2018-11-08 00:05:02 +08:00
2021-05-14 17:00:46 +08:00
mbedtls_printf("\n");
2018-11-08 00:05:02 +08:00
}
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return (ret != 0);
2018-11-08 00:05:02 +08:00
}
#endif /* MBEDTLS_SELF_TEST */
#endif /* MBEDTLS_ENTROPY_C */