mcuboot/boot/zephyr/os.c

64 lines
1.8 KiB
C

/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
#include <zephyr.h>
#include <string.h>
#include "os/os_heap.h"
#ifdef CONFIG_BOOT_USE_MBEDTLS
#include <mbedtls/platform.h>
#include <mbedtls/memory_buffer_alloc.h>
/*
* This is the heap for mbed TLS. The value needed depends on the key
* size and algorithm used.
*
* - RSA-2048 signing without encryption is known to work well with 6144 bytes;
* - When using RSA-2048-OAEP encryption + RSA-2048 signing, or RSA-3072
* signing (no encryption) 10240 bytes seems to be enough.
*
* NOTE: RSA-3072 signing + RSA-2048-OAEP might require growing the size...
*/
#if (CONFIG_BOOT_SIGNATURE_TYPE_RSA_LEN == 2048) && !defined(CONFIG_BOOT_ENCRYPT_RSA)
#define CRYPTO_HEAP_SIZE 6144
#else
# if !defined(MBEDTLS_RSA_NO_CRT)
# define CRYPTO_HEAP_SIZE 10240
# else
# define CRYPTO_HEAP_SIZE 16384
# endif
#endif
static unsigned char mempool[CRYPTO_HEAP_SIZE];
/*
* Initialize mbedtls to be able to use the local heap.
*/
void os_heap_init(void)
{
mbedtls_memory_buffer_alloc_init(mempool, sizeof(mempool));
}
#else
void os_heap_init(void)
{
}
#endif