ON Semiconductor / mbed-os

Important changes to repositories hosted on mbed.com

Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.

To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.

It is also possible to export all your personal repositories from the account settings page.

Dependents:   mbed-TFT-example-NCS36510 mbed-Accelerometer-example-NCS36510 mbed-Accelerometer-example-NCS36510

targets/TARGET_Maxim/TARGET_MAX32625/mxc/aes.c@0:098463de4c5d, 2017-01-25 (annotated)

Committer:
group-onsemi
Date:
Wed Jan 25 20:34:15 2017 +0000
Revision:
0:098463de4c5d
Initial commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
group-onsemi 0:098463de4c5d 1 /**
group-onsemi 0:098463de4c5d 2 * @file aes.c
group-onsemi 0:098463de4c5d 3 * @brief This file contains the function implementations for the Advanced
group-onsemi 0:098463de4c5d 4 * Encryption Standard (AES) peripheral module.
group-onsemi 0:098463de4c5d 5 */
group-onsemi 0:098463de4c5d 6
group-onsemi 0:098463de4c5d 7 /* ****************************************************************************
group-onsemi 0:098463de4c5d 8 * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
group-onsemi 0:098463de4c5d 9 *
group-onsemi 0:098463de4c5d 10 * Permission is hereby granted, free of charge, to any person obtaining a
group-onsemi 0:098463de4c5d 11 * copy of this software and associated documentation files (the "Software"),
group-onsemi 0:098463de4c5d 12 * to deal in the Software without restriction, including without limitation
group-onsemi 0:098463de4c5d 13 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
group-onsemi 0:098463de4c5d 14 * and/or sell copies of the Software, and to permit persons to whom the
group-onsemi 0:098463de4c5d 15 * Software is furnished to do so, subject to the following conditions:
group-onsemi 0:098463de4c5d 16 *
group-onsemi 0:098463de4c5d 17 * The above copyright notice and this permission notice shall be included
group-onsemi 0:098463de4c5d 18 * in all copies or substantial portions of the Software.
group-onsemi 0:098463de4c5d 19 *
group-onsemi 0:098463de4c5d 20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
group-onsemi 0:098463de4c5d 21 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
group-onsemi 0:098463de4c5d 22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
group-onsemi 0:098463de4c5d 23 * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
group-onsemi 0:098463de4c5d 24 * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
group-onsemi 0:098463de4c5d 25 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
group-onsemi 0:098463de4c5d 26 * OTHER DEALINGS IN THE SOFTWARE.
group-onsemi 0:098463de4c5d 27 *
group-onsemi 0:098463de4c5d 28 * Except as contained in this notice, the name of Maxim Integrated
group-onsemi 0:098463de4c5d 29 * Products, Inc. shall not be used except as stated in the Maxim Integrated
group-onsemi 0:098463de4c5d 30 * Products, Inc. Branding Policy.
group-onsemi 0:098463de4c5d 31 *
group-onsemi 0:098463de4c5d 32 * The mere transfer of this software does not imply any licenses
group-onsemi 0:098463de4c5d 33 * of trade secrets, proprietary technology, copyrights, patents,
group-onsemi 0:098463de4c5d 34 * trademarks, maskwork rights, or any other form of intellectual
group-onsemi 0:098463de4c5d 35 * property whatsoever. Maxim Integrated Products, Inc. retains all
group-onsemi 0:098463de4c5d 36 * ownership rights.
group-onsemi 0:098463de4c5d 37 *
group-onsemi 0:098463de4c5d 38 * $Date: 2016-08-02 13:39:05 -0500 (Tue, 02 Aug 2016) $
group-onsemi 0:098463de4c5d 39 * $Revision: 23894 $
group-onsemi 0:098463de4c5d 40 *
group-onsemi 0:098463de4c5d 41 *************************************************************************** */
group-onsemi 0:098463de4c5d 42
group-onsemi 0:098463de4c5d 43 /* **** Includes **** */
group-onsemi 0:098463de4c5d 44 #include <string.h> /* Included for memcpy() & #includes stddef for NULL */
group-onsemi 0:098463de4c5d 45
group-onsemi 0:098463de4c5d 46 #include "mxc_config.h"
group-onsemi 0:098463de4c5d 47 #include "aes.h"
group-onsemi 0:098463de4c5d 48
group-onsemi 0:098463de4c5d 49 /**
group-onsemi 0:098463de4c5d 50 * @ingroup aes
group-onsemi 0:098463de4c5d 51 * @{
group-onsemi 0:098463de4c5d 52 */
group-onsemi 0:098463de4c5d 53
group-onsemi 0:098463de4c5d 54 /* **** Definitions **** */
group-onsemi 0:098463de4c5d 55
group-onsemi 0:098463de4c5d 56 /* **** Globals **** */
group-onsemi 0:098463de4c5d 57
group-onsemi 0:098463de4c5d 58 /* **** Local Function Prototypes **** */
group-onsemi 0:098463de4c5d 59 static int aes_memcpy32(uint32_t *out, uint32_t *in, unsigned int count);
group-onsemi 0:098463de4c5d 60
group-onsemi 0:098463de4c5d 61 /* **** Functions **** */
group-onsemi 0:098463de4c5d 62
group-onsemi 0:098463de4c5d 63 /* ************************************************************************* */
group-onsemi 0:098463de4c5d 64 int AES_SetKey(const uint8_t *key, mxc_aes_mode_t mode)
group-onsemi 0:098463de4c5d 65 {
group-onsemi 0:098463de4c5d 66 unsigned int len;
group-onsemi 0:098463de4c5d 67
group-onsemi 0:098463de4c5d 68 /* Erase any existing key */
group-onsemi 0:098463de4c5d 69 MXC_AES_MEM->key[7] = MXC_AES_MEM->key[6] = MXC_AES_MEM->key[5] = MXC_AES_MEM->key[4] \
group-onsemi 0:098463de4c5d 70 = MXC_AES_MEM->key[3] = MXC_AES_MEM->key[2] = MXC_AES_MEM->key[1] = MXC_AES_MEM->key[0] \
group-onsemi 0:098463de4c5d 71 = 0x00000000;
group-onsemi 0:098463de4c5d 72
group-onsemi 0:098463de4c5d 73 /* Determine length of key */
group-onsemi 0:098463de4c5d 74 if (mode == MXC_E_AES_MODE_256) {
group-onsemi 0:098463de4c5d 75 len = MXC_AES_KEY_256_LEN;
group-onsemi 0:098463de4c5d 76 } else if (mode == MXC_E_AES_MODE_192) {
group-onsemi 0:098463de4c5d 77 len = MXC_AES_KEY_192_LEN;
group-onsemi 0:098463de4c5d 78 } else if (mode == MXC_E_AES_MODE_128) {
group-onsemi 0:098463de4c5d 79 len = MXC_AES_KEY_128_LEN;
group-onsemi 0:098463de4c5d 80 } else {
group-onsemi 0:098463de4c5d 81 return E_BAD_PARAM;
group-onsemi 0:098463de4c5d 82 }
group-onsemi 0:098463de4c5d 83
group-onsemi 0:098463de4c5d 84 /* Load new key, based on key mode */
group-onsemi 0:098463de4c5d 85 if (aes_memcpy32((uint32_t *)MXC_AES_MEM->key, (uint32_t *)key, len / sizeof(uint32_t)) < 0) {
group-onsemi 0:098463de4c5d 86 return E_NULL_PTR;
group-onsemi 0:098463de4c5d 87 }
group-onsemi 0:098463de4c5d 88
group-onsemi 0:098463de4c5d 89 return E_SUCCESS;
group-onsemi 0:098463de4c5d 90 }
group-onsemi 0:098463de4c5d 91
group-onsemi 0:098463de4c5d 92 /* ************************************************************************* */
group-onsemi 0:098463de4c5d 93 int AES_ECBOp(const uint8_t *in, uint8_t *out, mxc_aes_mode_t mode, mxc_aes_dir_t dir)
group-onsemi 0:098463de4c5d 94 {
group-onsemi 0:098463de4c5d 95 /* Output array can't be a NULL, unless we are in _ASYNC mode */
group-onsemi 0:098463de4c5d 96 if ((out == NULL)
group-onsemi 0:098463de4c5d 97 && ((dir != MXC_E_AES_ENCRYPT_ASYNC) && (dir != MXC_E_AES_DECRYPT_ASYNC))) {
group-onsemi 0:098463de4c5d 98 return E_NULL_PTR;
group-onsemi 0:098463de4c5d 99 }
group-onsemi 0:098463de4c5d 100
group-onsemi 0:098463de4c5d 101 /* Another encryption is already in progress */
group-onsemi 0:098463de4c5d 102 if (MXC_AES->ctrl & MXC_F_AES_CTRL_START) {
group-onsemi 0:098463de4c5d 103 return E_BUSY;
group-onsemi 0:098463de4c5d 104 }
group-onsemi 0:098463de4c5d 105
group-onsemi 0:098463de4c5d 106 /* Clear interrupt flag and any existing configuration*/
group-onsemi 0:098463de4c5d 107 MXC_AES->ctrl = MXC_F_AES_CTRL_INTFL;
group-onsemi 0:098463de4c5d 108
group-onsemi 0:098463de4c5d 109 /* Select key size & direction
group-onsemi 0:098463de4c5d 110 *
group-onsemi 0:098463de4c5d 111 * Note: This is done first to detect argument errors, before sensitive data
group-onsemi 0:098463de4c5d 112 * is loaded into AES_MEM block
group-onsemi 0:098463de4c5d 113 *
group-onsemi 0:098463de4c5d 114 */
group-onsemi 0:098463de4c5d 115 switch (mode) {
group-onsemi 0:098463de4c5d 116 case MXC_E_AES_MODE_128:
group-onsemi 0:098463de4c5d 117 MXC_AES->ctrl |= MXC_S_AES_CTRL_KEY_SIZE_128;
group-onsemi 0:098463de4c5d 118 break;
group-onsemi 0:098463de4c5d 119
group-onsemi 0:098463de4c5d 120 case MXC_E_AES_MODE_192:
group-onsemi 0:098463de4c5d 121 MXC_AES->ctrl |= MXC_S_AES_CTRL_KEY_SIZE_192;
group-onsemi 0:098463de4c5d 122 break;
group-onsemi 0:098463de4c5d 123
group-onsemi 0:098463de4c5d 124 case MXC_E_AES_MODE_256:
group-onsemi 0:098463de4c5d 125 MXC_AES->ctrl |= MXC_S_AES_CTRL_KEY_SIZE_256;
group-onsemi 0:098463de4c5d 126 break;
group-onsemi 0:098463de4c5d 127
group-onsemi 0:098463de4c5d 128 default:
group-onsemi 0:098463de4c5d 129 return E_BAD_PARAM;
group-onsemi 0:098463de4c5d 130 }
group-onsemi 0:098463de4c5d 131
group-onsemi 0:098463de4c5d 132 switch (dir) {
group-onsemi 0:098463de4c5d 133 case MXC_E_AES_ENCRYPT:
group-onsemi 0:098463de4c5d 134 case MXC_E_AES_ENCRYPT_ASYNC:
group-onsemi 0:098463de4c5d 135 MXC_AES->ctrl |= MXC_S_AES_CTRL_ENCRYPT_MODE;
group-onsemi 0:098463de4c5d 136 break;
group-onsemi 0:098463de4c5d 137
group-onsemi 0:098463de4c5d 138 case MXC_E_AES_DECRYPT:
group-onsemi 0:098463de4c5d 139 case MXC_E_AES_DECRYPT_ASYNC:
group-onsemi 0:098463de4c5d 140 MXC_AES->ctrl |= MXC_S_AES_CTRL_DECRYPT_MODE;
group-onsemi 0:098463de4c5d 141 break;
group-onsemi 0:098463de4c5d 142
group-onsemi 0:098463de4c5d 143 default:
group-onsemi 0:098463de4c5d 144 return E_BAD_PARAM;
group-onsemi 0:098463de4c5d 145 }
group-onsemi 0:098463de4c5d 146
group-onsemi 0:098463de4c5d 147 /* If non-blocking mode has been selected, interrupts are automatically enabled */
group-onsemi 0:098463de4c5d 148 if ((dir == MXC_E_AES_ENCRYPT_ASYNC) ||
group-onsemi 0:098463de4c5d 149 (dir == MXC_E_AES_DECRYPT_ASYNC)) {
group-onsemi 0:098463de4c5d 150 MXC_AES->ctrl |= MXC_F_AES_CTRL_INTEN;
group-onsemi 0:098463de4c5d 151 }
group-onsemi 0:098463de4c5d 152
group-onsemi 0:098463de4c5d 153 /* Load input into engine */
group-onsemi 0:098463de4c5d 154 if (aes_memcpy32((uint32_t *)MXC_AES_MEM->inp, (uint32_t *)in, MXC_AES_DATA_LEN / sizeof(uint32_t)) < 0) {
group-onsemi 0:098463de4c5d 155 return E_NULL_PTR;
group-onsemi 0:098463de4c5d 156 }
group-onsemi 0:098463de4c5d 157
group-onsemi 0:098463de4c5d 158 /* Start operation */
group-onsemi 0:098463de4c5d 159 MXC_AES->ctrl |= MXC_F_AES_CTRL_START;
group-onsemi 0:098463de4c5d 160
group-onsemi 0:098463de4c5d 161 /* Block, waiting on engine to complete, or fall through if non-blocking */
group-onsemi 0:098463de4c5d 162 if ((dir != MXC_E_AES_ENCRYPT_ASYNC) &&
group-onsemi 0:098463de4c5d 163 (dir != MXC_E_AES_DECRYPT_ASYNC)) {
group-onsemi 0:098463de4c5d 164 while (MXC_AES->ctrl & MXC_F_AES_CTRL_START) {
group-onsemi 0:098463de4c5d 165 /* Ensure that this wait loop is not optimized out */
group-onsemi 0:098463de4c5d 166 __NOP();
group-onsemi 0:098463de4c5d 167 }
group-onsemi 0:098463de4c5d 168
group-onsemi 0:098463de4c5d 169 /* Get output from engine */
group-onsemi 0:098463de4c5d 170 return AES_GetOutput(out);
group-onsemi 0:098463de4c5d 171 }
group-onsemi 0:098463de4c5d 172
group-onsemi 0:098463de4c5d 173 return E_SUCCESS;
group-onsemi 0:098463de4c5d 174 }
group-onsemi 0:098463de4c5d 175
group-onsemi 0:098463de4c5d 176 /* ************************************************************************* */
group-onsemi 0:098463de4c5d 177 int AES_GetOutput(uint8_t *out)
group-onsemi 0:098463de4c5d 178 {
group-onsemi 0:098463de4c5d 179 /* Don't read it out of the AES memory unless engine is idle */
group-onsemi 0:098463de4c5d 180 if (MXC_AES->ctrl & MXC_F_AES_CTRL_START) {
group-onsemi 0:098463de4c5d 181 return E_BUSY;
group-onsemi 0:098463de4c5d 182 }
group-onsemi 0:098463de4c5d 183
group-onsemi 0:098463de4c5d 184 /* Pull out result */
group-onsemi 0:098463de4c5d 185 if (aes_memcpy32((uint32_t *)out, (uint32_t *)MXC_AES_MEM->out, MXC_AES_DATA_LEN / sizeof(uint32_t)) < 0) {
group-onsemi 0:098463de4c5d 186 return E_NULL_PTR;
group-onsemi 0:098463de4c5d 187 }
group-onsemi 0:098463de4c5d 188
group-onsemi 0:098463de4c5d 189 /* Clear interrupt flag, write 1 to clear */
group-onsemi 0:098463de4c5d 190 MXC_AES->ctrl |= MXC_F_AES_CTRL_INTFL;
group-onsemi 0:098463de4c5d 191
group-onsemi 0:098463de4c5d 192 return E_SUCCESS;
group-onsemi 0:098463de4c5d 193 }
group-onsemi 0:098463de4c5d 194
group-onsemi 0:098463de4c5d 195 /**
group-onsemi 0:098463de4c5d 196 * @internal This memory copy is used only by the AES module to avoid data leakage by the standard C library.
group-onsemi 0:098463de4c5d 197 * Copy count number of 32-bit locations from in to out
group-onsemi 0:098463de4c5d 198 */
group-onsemi 0:098463de4c5d 199 static int aes_memcpy32(uint32_t *out, uint32_t *in, unsigned int count)
group-onsemi 0:098463de4c5d 200 {
group-onsemi 0:098463de4c5d 201 if ((out == NULL) || (in == NULL)) {
group-onsemi 0:098463de4c5d 202 /* Invalid arguments, but is internal-only so don't use error codes */
group-onsemi 0:098463de4c5d 203 return -1;
group-onsemi 0:098463de4c5d 204 }
group-onsemi 0:098463de4c5d 205
group-onsemi 0:098463de4c5d 206 while (count--) {
group-onsemi 0:098463de4c5d 207 *out++ = *in++;
group-onsemi 0:098463de4c5d 208 }
group-onsemi 0:098463de4c5d 209
group-onsemi 0:098463de4c5d 210 return 0;
group-onsemi 0:098463de4c5d 211 }
group-onsemi 0:098463de4c5d 212
group-onsemi 0:098463de4c5d 213 /**@} end of group aes */