mbedtls/yotta/data/example-hashing/main.cpp
2016-03-17 13:55:07 +00:00

178 lines
4.8 KiB
C++

/*
* Hello world example of using the hashing functions of mbed TLS
*
* Copyright (C) 2006-2015, 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)
*/
/*
* This program illustrates various ways of hashing a buffer.
* You normally need only one of these two includes.
*/
#include "mbedtls/sha256.h" /* SHA-256 only */
#include "mbedtls/md.h" /* generic interface */
#if defined(TARGET_LIKE_MBED)
#include "mbed-drivers/mbed.h"
#endif
#include <cstdio>
static void print_hex(const char *title, const unsigned char buf[], size_t len)
{
printf("%s: ", title);
for (size_t i = 0; i < len; i++)
printf("%02x", buf[i]);
printf("\r\n");
}
static const char hello_str[] = "Hello, world!";
static const unsigned char *hello_buffer = (const unsigned char *) hello_str;
static const size_t hello_len = sizeof hello_str - 1;
int example(void)
{
printf( "\r\n\r\n" );
/*
* Method 1: use all-in-one function of a specific SHA-xxx module
*/
unsigned char output1[32]; /* SHA-256 outputs 32 bytes */
/* 0 here means use the full SHA-256, not the SHA-224 variant */
mbedtls_sha256(hello_buffer, hello_len, output1, 0);
print_hex("Method 1", output1, sizeof output1);
/*
* Method 2: use the streaming interface of a specific SHA-xxx module
* This is useful if we get our input piecewise.
*/
unsigned char output2[32];
mbedtls_sha256_context ctx2;
mbedtls_sha256_init(&ctx2);
mbedtls_sha256_starts(&ctx2, 0); /* SHA-256, not 224 */
/* Simulating multiple fragments */
mbedtls_sha256_update(&ctx2, hello_buffer, 1);
mbedtls_sha256_update(&ctx2, hello_buffer + 1, 1);
mbedtls_sha256_update(&ctx2, hello_buffer + 2, hello_len - 2);
mbedtls_sha256_finish(&ctx2, output2);
print_hex("Method 2", output2, sizeof output2);
/* Or you could re-use the context by doing mbedtls_sha256_starts() again */
mbedtls_sha256_free(&ctx2);
/*
* Method 3: use all-in-one function of the generice interface
*/
unsigned char output3[MBEDTLS_MD_MAX_SIZE]; /* Enough for any hash */
/* Can easily pick any hash you want, by identifier */
const mbedtls_md_info_t *md_info3 = mbedtls_md_info_from_type(MBEDTLS_MD_SHA256);
if (md_info3 == NULL)
{
printf("SHA256 not available\r\n");
return 1;
}
int ret3 = mbedtls_md(md_info3, hello_buffer, hello_len, output3);
if (ret3 != 0)
{
printf("md() returned -0x%04X\r\n", -ret3);
return 1;
}
print_hex("Method 3", output3, mbedtls_md_get_size(md_info3));
/*
* Method 4: streaming & generic interface
*/
unsigned char output4[MBEDTLS_MD_MAX_SIZE]; /* Enough for any hash */
const mbedtls_md_info_t *md_info4 = mbedtls_md_info_from_type(MBEDTLS_MD_SHA256);
if (md_info4 == NULL)
{
printf("SHA256 not available\r\n");
return 1;
}
mbedtls_md_context_t ctx4;
mbedtls_md_init(&ctx4);
int ret4 = mbedtls_md_init_ctx(&ctx4, md_info4);
if (ret4 != 0)
{
printf("md_init_ctx() returned -0x%04X\r\n", -ret4);
return 1;
}
mbedtls_md_starts(&ctx4);
/* Simulating multiple fragments */
mbedtls_md_update(&ctx4, hello_buffer, 1);
mbedtls_md_update(&ctx4, hello_buffer + 1, 1);
mbedtls_md_update(&ctx4, hello_buffer + 2, hello_len - 2);
mbedtls_md_finish(&ctx4, output4);
print_hex("Method 4", output4, mbedtls_md_get_size(md_info4));
/* Or you could re-use the context by doing mbedtls_md_starts() again */
mbedtls_md_free(&ctx4);
printf("\r\nDONE\r\n");
return 0;
}
#if defined(TARGET_LIKE_MBED)
#include "mbed-drivers/test_env.h"
#include "minar/minar.h"
static void run() {
MBED_HOSTTEST_TIMEOUT(10);
MBED_HOSTTEST_SELECT(default);
MBED_HOSTTEST_DESCRIPTION(mbed TLS example on hashing);
MBED_HOSTTEST_START("MBEDTLS_EX_HASHING");
MBED_HOSTTEST_RESULT(example() == 0);
}
void app_start(int, char*[]) {
/* Use 115200 bps for consistency with other examples */
get_stdio_serial().baud(115200);
minar::Scheduler::postCallback(mbed::util::FunctionPointer0<void>(run).bind());
}
#else
int main() {
return example();
}
#endif