mbed library sources. Supersedes mbed-src. Edited target satm32f446 for user USART3 pins
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Diff: targets/TARGET_Maxim/TARGET_MAX32620C/mxc/aes.c
- Revision:
- 186:707f6e361f3e
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/TARGET_Maxim/TARGET_MAX32620C/mxc/aes.c Fri Jun 22 16:45:37 2018 +0100 @@ -0,0 +1,214 @@ +/** + * @file + * @brief This file contains the function implementations for the Advanced + * Encryption Standard (AES) peripheral module. + */ + +/* **************************************************************************** + * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. + * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES + * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + * + * Except as contained in this notice, the name of Maxim Integrated + * Products, Inc. shall not be used except as stated in the Maxim Integrated + * Products, Inc. Branding Policy. + * + * The mere transfer of this software does not imply any licenses + * of trade secrets, proprietary technology, copyrights, patents, + * trademarks, maskwork rights, or any other form of intellectual + * property whatsoever. Maxim Integrated Products, Inc. retains all + * ownership rights. + * + * $Date: 2016-09-09 12:50:17 -0500 (Fri, 09 Sep 2016) $ + * $Revision: 24348 $ + * + *************************************************************************** */ + +/* **** Includes **** */ +#include <string.h> /* Included for memcpy() & #includes stddef for NULL */ + +#include "mxc_config.h" +#include "aes.h" +#include "nvic_table.h" + +/** + * @ingroup aes + * @{ + */ + +/* **** Definitions **** */ + +/* **** Globals **** */ + +/* **** Local Function Prototypes **** */ +static int aes_memcpy32(uint32_t *out, uint32_t *in, unsigned int count); + +/* **** Functions **** */ + +/* ************************************************************************* */ +int AES_SetKey(const uint8_t *key, mxc_aes_mode_t mode) +{ + unsigned int len; + + /* Erase any existing key */ + MXC_AES_MEM->key[7] = MXC_AES_MEM->key[6] = MXC_AES_MEM->key[5] = MXC_AES_MEM->key[4] \ + = MXC_AES_MEM->key[3] = MXC_AES_MEM->key[2] = MXC_AES_MEM->key[1] = MXC_AES_MEM->key[0] \ + = 0x00000000; + + /* Determine length of key */ + if (mode == MXC_E_AES_MODE_256) { + len = MXC_AES_KEY_256_LEN; + } else if (mode == MXC_E_AES_MODE_192) { + len = MXC_AES_KEY_192_LEN; + } else if (mode == MXC_E_AES_MODE_128) { + len = MXC_AES_KEY_128_LEN; + } else { + return E_BAD_PARAM; + } + + /* Load new key, based on key mode */ + if (aes_memcpy32((uint32_t *)MXC_AES_MEM->key, (uint32_t *)key, len / sizeof(uint32_t)) < 0) { + return E_NULL_PTR; + } + + return E_SUCCESS; +} + +/* ************************************************************************* */ +int AES_ECBOp(const uint8_t *in, uint8_t *out, mxc_aes_mode_t mode, mxc_aes_dir_t dir) +{ + /* Output array can't be a NULL, unless we are in _ASYNC mode */ + if ((out == NULL) + && ((dir != MXC_E_AES_ENCRYPT_ASYNC) && (dir != MXC_E_AES_DECRYPT_ASYNC))) { + return E_NULL_PTR; + } + + /* Another encryption is already in progress */ + if (MXC_AES->ctrl & MXC_F_AES_CTRL_START) { + return E_BUSY; + } + + /* Clear interrupt flag and any existing configuration*/ + MXC_AES->ctrl = MXC_F_AES_CTRL_INTFL; + + /* Select key size & direction + * + * Note: This is done first to detect argument errors, before sensitive data + * is loaded into AES_MEM block + * + */ + switch (mode) { + case MXC_E_AES_MODE_128: + MXC_AES->ctrl |= MXC_S_AES_CTRL_KEY_SIZE_128; + break; + + case MXC_E_AES_MODE_192: + MXC_AES->ctrl |= MXC_S_AES_CTRL_KEY_SIZE_192; + break; + + case MXC_E_AES_MODE_256: + MXC_AES->ctrl |= MXC_S_AES_CTRL_KEY_SIZE_256; + break; + + default: + return E_BAD_PARAM; + } + + switch (dir) { + case MXC_E_AES_ENCRYPT: + case MXC_E_AES_ENCRYPT_ASYNC: + MXC_AES->ctrl |= MXC_S_AES_CTRL_ENCRYPT_MODE; + break; + + case MXC_E_AES_DECRYPT: + case MXC_E_AES_DECRYPT_ASYNC: + MXC_AES->ctrl |= MXC_S_AES_CTRL_DECRYPT_MODE; + break; + + default: + return E_BAD_PARAM; + } + + /* If non-blocking mode has been selected, interrupts are automatically enabled */ + if ((dir == MXC_E_AES_ENCRYPT_ASYNC) || + (dir == MXC_E_AES_DECRYPT_ASYNC)) { + MXC_AES->ctrl |= MXC_F_AES_CTRL_INTEN; + } + + /* Load input into engine */ + if (aes_memcpy32((uint32_t *)MXC_AES_MEM->inp, (uint32_t *)in, MXC_AES_DATA_LEN / sizeof(uint32_t)) < 0) { + return E_NULL_PTR; + } + + /* Start operation */ + MXC_AES->ctrl |= MXC_F_AES_CTRL_START; + + /* Block, waiting on engine to complete, or fall through if non-blocking */ + if ((dir != MXC_E_AES_ENCRYPT_ASYNC) && + (dir != MXC_E_AES_DECRYPT_ASYNC)) { + while (MXC_AES->ctrl & MXC_F_AES_CTRL_START) { + /* Ensure that this wait loop is not optimized out */ + __NOP(); + } + + /* Get output from engine */ + return AES_GetOutput(out); + } + + return E_SUCCESS; +} + +/* ************************************************************************* */ +int AES_GetOutput(uint8_t *out) +{ + /* Don't read it out of the AES memory unless engine is idle */ + if (MXC_AES->ctrl & MXC_F_AES_CTRL_START) { + return E_BUSY; + } + + /* Pull out result */ + if (aes_memcpy32((uint32_t *)out, (uint32_t *)MXC_AES_MEM->out, MXC_AES_DATA_LEN / sizeof(uint32_t)) < 0) { + return E_NULL_PTR; + } + + /* Clear interrupt flag, write 1 to clear */ + MXC_AES->ctrl |= MXC_F_AES_CTRL_INTFL; + + return E_SUCCESS; +} + +/** + * @internal This memory copy is used only by the AES module to avoid data leakage by the standard C library. + * Copy count number of 32-bit locations from in to out + */ +static int aes_memcpy32(uint32_t *out, uint32_t *in, unsigned int count) +{ + if ((out == NULL) || (in == NULL)) { + /* Invalid arguments, but is internal-only so don't use error codes */ + return -1; + } + + while (count--) { + *out++ = *in++; + } + + return 0; +} + +/**@} end of group aes */