lixian
/
doubao_chat
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
doubao_chat/lib/net/mbedtls_2_2_1/library/entropy.c

561 lines
15 KiB
C
Raw Permalink Blame History

/*
* Entropy accumulator implementation
*
* Copyright (C) 2006-2016, ARM Limited, All Rights Reserved
* 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.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/mbedtls_config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#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 <string.h>
#if defined(MBEDTLS_FS_IO)
#include <stdio.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
/* Implementation that should never be optimized out by the compiler */
static void mbedtls_zeroize(void *v, size_t n)
{
volatile unsigned char *p = v;
while (n--) {
*p++ = 0;
}
}
#define ENTROPY_MAX_LOOP 256 /**< Maximum amount to loop before error */
void mbedtls_entropy_init(mbedtls_entropy_context *ctx)
{
memset(ctx, 0, sizeof(mbedtls_entropy_context));
#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_init(&ctx->mutex);
#endif
#if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
mbedtls_sha512_starts(&ctx->accumulator, 0);
#else
mbedtls_sha256_starts(&ctx->accumulator, 0);
#endif
#if defined(MBEDTLS_HAVEGE_C)
mbedtls_havege_init(&ctx->havege_data);
#endif
#if defined(MBEDTLS_TEST_NULL_ENTROPY)
mbedtls_entropy_add_source(ctx, mbedtls_null_entropy_poll, NULL,
1, MBEDTLS_ENTROPY_SOURCE_STRONG);
#endif
#if !defined(MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES)
#if !defined(MBEDTLS_NO_PLATFORM_ENTROPY)
mbedtls_entropy_add_source(ctx, mbedtls_platform_entropy_poll, NULL,
MBEDTLS_ENTROPY_MIN_PLATFORM,
MBEDTLS_ENTROPY_SOURCE_STRONG);
#endif
#if defined(MBEDTLS_TIMING_C)
mbedtls_entropy_add_source(ctx, mbedtls_hardclock_poll, NULL,
MBEDTLS_ENTROPY_MIN_HARDCLOCK,
MBEDTLS_ENTROPY_SOURCE_WEAK);
#endif
#if defined(MBEDTLS_HAVEGE_C)
mbedtls_entropy_add_source(ctx, mbedtls_havege_poll, &ctx->havege_data,
MBEDTLS_ENTROPY_MIN_HAVEGE,
MBEDTLS_ENTROPY_SOURCE_STRONG);
#endif
#if defined(MBEDTLS_ENTROPY_HARDWARE_ALT)
mbedtls_entropy_add_source(ctx, mbedtls_hardware_poll, NULL,
MBEDTLS_ENTROPY_MIN_HARDWARE,
MBEDTLS_ENTROPY_SOURCE_STRONG);
#endif
#if defined(MBEDTLS_ENTROPY_NV_SEED)
mbedtls_entropy_add_source(ctx, mbedtls_nv_seed_poll, NULL,
MBEDTLS_ENTROPY_BLOCK_SIZE,
MBEDTLS_ENTROPY_SOURCE_STRONG);
#endif
#endif /* MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES */
}
void mbedtls_entropy_free(mbedtls_entropy_context *ctx)
{
#if defined(MBEDTLS_HAVEGE_C)
mbedtls_havege_free(&ctx->havege_data);
#endif
#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_free(&ctx->mutex);
#endif
mbedtls_zeroize(ctx, sizeof(mbedtls_entropy_context));
}
int mbedtls_entropy_add_source(mbedtls_entropy_context *ctx,
mbedtls_entropy_f_source_ptr f_source, void *p_source,
size_t threshold, int strong)
{
int index, ret = 0;
#if defined(MBEDTLS_THREADING_C)
if ((ret = mbedtls_mutex_lock(&ctx->mutex)) != 0) {
return (ret);
}
#endif
index = ctx->source_count;
if (index >= MBEDTLS_ENTROPY_MAX_SOURCES) {
ret = MBEDTLS_ERR_ENTROPY_MAX_SOURCES;
goto exit;
}
ctx->source[index].f_source = f_source;
ctx->source[index].p_source = p_source;
ctx->source[index].threshold = threshold;
ctx->source[index].strong = strong;
ctx->source_count++;
exit:
#if defined(MBEDTLS_THREADING_C)
if (mbedtls_mutex_unlock(&ctx->mutex) != 0) {
return (MBEDTLS_ERR_THREADING_MUTEX_ERROR);
}
#endif
return (ret);
}
/*
* Entropy accumulator update
*/
static int entropy_update(mbedtls_entropy_context *ctx, unsigned char source_id,
const unsigned char *data, size_t len)
{
unsigned char header[2];
unsigned char tmp[MBEDTLS_ENTROPY_BLOCK_SIZE];
size_t use_len = len;
const unsigned char *p = data;
if (use_len > MBEDTLS_ENTROPY_BLOCK_SIZE) {
#if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
mbedtls_sha512(data, len, tmp, 0);
#else
mbedtls_sha256(data, len, tmp, 0);
#endif
p = tmp;
use_len = MBEDTLS_ENTROPY_BLOCK_SIZE;
}
header[0] = source_id;
header[1] = use_len & 0xFF;
#if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
mbedtls_sha512_update(&ctx->accumulator, header, 2);
mbedtls_sha512_update(&ctx->accumulator, p, use_len);
#else
mbedtls_sha256_update(&ctx->accumulator, header, 2);
mbedtls_sha256_update(&ctx->accumulator, p, use_len);
#endif
return (0);
}
int mbedtls_entropy_update_manual(mbedtls_entropy_context *ctx,
const unsigned char *data, size_t len)
{
int ret;
#if defined(MBEDTLS_THREADING_C)
if ((ret = mbedtls_mutex_lock(&ctx->mutex)) != 0) {
return (ret);
}
#endif
ret = entropy_update(ctx, MBEDTLS_ENTROPY_SOURCE_MANUAL, data, len);
#if defined(MBEDTLS_THREADING_C)
if (mbedtls_mutex_unlock(&ctx->mutex) != 0) {
return (MBEDTLS_ERR_THREADING_MUTEX_ERROR);
}
#endif
return (ret);
}
/*
* Run through the different sources to add entropy to our accumulator
*/
static int entropy_gather_internal(mbedtls_entropy_context *ctx)
{
int ret, i, have_one_strong = 0;
unsigned char buf[MBEDTLS_ENTROPY_MAX_GATHER];
size_t olen;
if (ctx->source_count == 0) {
return (MBEDTLS_ERR_ENTROPY_NO_SOURCES_DEFINED);
}
/*
* Run through our entropy sources
*/
for (i = 0; i < ctx->source_count; i++) {
if (ctx->source[i].strong == MBEDTLS_ENTROPY_SOURCE_STRONG) {
have_one_strong = 1;
}
olen = 0;
if ((ret = ctx->source[i].f_source(ctx->source[i].p_source,
buf, MBEDTLS_ENTROPY_MAX_GATHER, &olen)) != 0) {
return (ret);
}
/*
* Add if we actually gathered something
*/
if (olen > 0) {
entropy_update(ctx, (unsigned char) i, buf, olen);
ctx->source[i].size += olen;
}
}
if (have_one_strong == 0) {
return (MBEDTLS_ERR_ENTROPY_NO_STRONG_SOURCE);
}
return (0);
}
/*
* Thread-safe wrapper for entropy_gather_internal()
*/
int mbedtls_entropy_gather(mbedtls_entropy_context *ctx)
{
int ret;
#if defined(MBEDTLS_THREADING_C)
if ((ret = mbedtls_mutex_lock(&ctx->mutex)) != 0) {
return (ret);
}
#endif
ret = entropy_gather_internal(ctx);
#if defined(MBEDTLS_THREADING_C)
if (mbedtls_mutex_unlock(&ctx->mutex) != 0) {
return (MBEDTLS_ERR_THREADING_MUTEX_ERROR);
}
#endif
return (ret);
}
int mbedtls_entropy_func(void *data, unsigned char *output, size_t len)
{
int ret, count = 0, i, done;
mbedtls_entropy_context *ctx = (mbedtls_entropy_context *) data;
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
if (len > MBEDTLS_ENTROPY_BLOCK_SIZE) {
return (MBEDTLS_ERR_ENTROPY_SOURCE_FAILED);
}
#if defined(MBEDTLS_ENTROPY_NV_SEED)
/* Update the NV entropy seed before generating any entropy for outside
* use.
*/
if (ctx->initial_entropy_run == 0) {
ctx->initial_entropy_run = 1;
if ((ret = mbedtls_entropy_update_nv_seed(ctx)) != 0) {
return (ret);
}
}
#endif
#if defined(MBEDTLS_THREADING_C)
if ((ret = mbedtls_mutex_lock(&ctx->mutex)) != 0) {
return (ret);
}
#endif
/*
* Always gather extra entropy before a call
*/
do {
if (count++ > ENTROPY_MAX_LOOP) {
ret = MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
goto exit;
}
if ((ret = entropy_gather_internal(ctx)) != 0) {
goto exit;
}
done = 1;
for (i = 0; i < ctx->source_count; i++)
if (ctx->source[i].size < ctx->source[i].threshold) {
done = 0;
}
} while (! done);
memset(buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE);
#if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
mbedtls_sha512_finish(&ctx->accumulator, buf);
/*
* Reset accumulator and counters and recycle existing entropy
*/
memset(&ctx->accumulator, 0, sizeof(mbedtls_sha512_context));
mbedtls_sha512_starts(&ctx->accumulator, 0);
mbedtls_sha512_update(&ctx->accumulator, buf, MBEDTLS_ENTROPY_BLOCK_SIZE);
/*
* Perform second SHA-512 on entropy
*/
mbedtls_sha512(buf, MBEDTLS_ENTROPY_BLOCK_SIZE, buf, 0);
#else /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */
mbedtls_sha256_finish(&ctx->accumulator, buf);
/*
* Reset accumulator and counters and recycle existing entropy
*/
memset(&ctx->accumulator, 0, sizeof(mbedtls_sha256_context));
mbedtls_sha256_starts(&ctx->accumulator, 0);
mbedtls_sha256_update(&ctx->accumulator, buf, MBEDTLS_ENTROPY_BLOCK_SIZE);
/*
* Perform second SHA-256 on entropy
*/
mbedtls_sha256(buf, MBEDTLS_ENTROPY_BLOCK_SIZE, buf, 0);
#endif /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */
for (i = 0; i < ctx->source_count; i++) {
ctx->source[i].size = 0;
}
memcpy(output, buf, len);
ret = 0;
exit:
#if defined(MBEDTLS_THREADING_C)
if (mbedtls_mutex_unlock(&ctx->mutex) != 0) {
return (MBEDTLS_ERR_THREADING_MUTEX_ERROR);
}
#endif
return (ret);
}
#if defined(MBEDTLS_ENTROPY_NV_SEED)
int mbedtls_entropy_update_nv_seed(mbedtls_entropy_context *ctx)
{
int ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
unsigned char buf[ MBEDTLS_ENTROPY_MAX_SEED_SIZE ];
/* Read new seed and write it to NV */
if ((ret = mbedtls_entropy_func(ctx, buf, MBEDTLS_ENTROPY_BLOCK_SIZE)) != 0) {
return (ret);
}
if (mbedtls_nv_seed_write(buf, MBEDTLS_ENTROPY_BLOCK_SIZE) < 0) {
return (MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR);
}
/* Manually update the remaining stream with a separator value to diverge */
memset(buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE);
mbedtls_entropy_update_manual(ctx, buf, MBEDTLS_ENTROPY_BLOCK_SIZE);
return (0);
}
#endif /* MBEDTLS_ENTROPY_NV_SEED */
#if defined(MBEDTLS_FS_IO)
int mbedtls_entropy_write_seed_file(mbedtls_entropy_context *ctx, const char *path)
{
int ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
FILE *f;
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
if ((f = fopen(path, "wb")) == NULL) {
return (MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR);
}
if ((ret = mbedtls_entropy_func(ctx, buf, MBEDTLS_ENTROPY_BLOCK_SIZE)) != 0) {
goto exit;
}
if (fwrite(buf, 1, MBEDTLS_ENTROPY_BLOCK_SIZE, f) != MBEDTLS_ENTROPY_BLOCK_SIZE) {
ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
goto exit;
}
ret = 0;
exit:
fclose(f);
return (ret);
}
int mbedtls_entropy_update_seed_file(mbedtls_entropy_context *ctx, const char *path)
{
FILE *f;
size_t n;
unsigned char buf[ MBEDTLS_ENTROPY_MAX_SEED_SIZE ];
if ((f = fopen(path, "rb")) == NULL) {
return (MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR);
}
fseek(f, 0, SEEK_END);
n = (size_t) ftell(f);
fseek(f, 0, SEEK_SET);
if (n > MBEDTLS_ENTROPY_MAX_SEED_SIZE) {
n = MBEDTLS_ENTROPY_MAX_SEED_SIZE;
}
if (fread(buf, 1, n, f) != n) {
fclose(f);
return (MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR);
}
fclose(f);
mbedtls_entropy_update_manual(ctx, buf, n);
return (mbedtls_entropy_write_seed_file(ctx, path));
}
#endif /* MBEDTLS_FS_IO */
#if defined(MBEDTLS_SELF_TEST)
/*
* Dummy source function
*/
static int entropy_dummy_source(void *data, unsigned char *output,
size_t len, size_t *olen)
{
((void) data);
memset(output, 0x2a, len);
*olen = len;
return (0);
}
/*
* 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.
*/
int mbedtls_entropy_self_test(int verbose)
{
int ret = 0;
mbedtls_entropy_context ctx;
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE] = { 0 };
unsigned char acc[MBEDTLS_ENTROPY_BLOCK_SIZE] = { 0 };
size_t i, j;
if (verbose != 0) {
mbedtls_printf(" ENTROPY test: ");
}
mbedtls_entropy_init(&ctx);
/* First do a gather to make sure we have default sources */
if ((ret = mbedtls_entropy_gather(&ctx)) != 0) {
goto cleanup;
}
ret = mbedtls_entropy_add_source(&ctx, entropy_dummy_source, NULL, 16,
MBEDTLS_ENTROPY_SOURCE_WEAK);
if (ret != 0) {
goto cleanup;
}
if ((ret = mbedtls_entropy_update_manual(&ctx, buf, sizeof buf)) != 0) {
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.
*/
for (i = 0; i < 8; i++) {
if ((ret = mbedtls_entropy_func(&ctx, buf, sizeof(buf))) != 0) {
goto cleanup;
}
for (j = 0; j < sizeof(buf); j++) {
acc[j] |= buf[j];
}
}
for (j = 0; j < sizeof(buf); j++) {
if (acc[j] == 0) {
ret = 1;
goto cleanup;
}
}
cleanup:
mbedtls_entropy_free(&ctx);
if (verbose != 0) {
if (ret != 0) {
mbedtls_printf("failed\n");
} else {
mbedtls_printf("passed\n");
}
mbedtls_printf("\n");
}
return (ret != 0);
}
#endif /* MBEDTLS_SELF_TEST */
#endif /* MBEDTLS_ENTROPY_C */
Reference in New Issue View Git Blame Copy Permalink