mbed official / mbed-dev

mbed library sources. Supersedes mbed-src.

Dependents:   Nucleo_Hello_Encoder BLE_iBeaconScan AM1805_DEMO DISCO-F429ZI_ExportTemplate1 ... more

targets/TARGET_Maxim/TARGET_MAX32620C/mxc/mxc_aes.c@189:f392fc9709a3, 2019-02-20 (annotated)

Committer:
AnnaBridge
Date:
Wed Feb 20 22:31:08 2019 +0000
Revision:
189:f392fc9709a3
Parent:
187:0387e8f68319 
mbed library release version 165

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Anna Bridge 186:707f6e361f3e 1 /**
Anna Bridge 186:707f6e361f3e 2 * @file
Anna Bridge 186:707f6e361f3e 3 * @brief This file contains the function implementations for the Advanced
Anna Bridge 186:707f6e361f3e 4 * Encryption Standard (AES) peripheral module.
Anna Bridge 186:707f6e361f3e 5 */
Anna Bridge 186:707f6e361f3e 6
Anna Bridge 186:707f6e361f3e 7 /* ****************************************************************************
Anna Bridge 186:707f6e361f3e 8 * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
Anna Bridge 186:707f6e361f3e 9 *
Anna Bridge 186:707f6e361f3e 10 * Permission is hereby granted, free of charge, to any person obtaining a
Anna Bridge 186:707f6e361f3e 11 * copy of this software and associated documentation files (the "Software"),
Anna Bridge 186:707f6e361f3e 12 * to deal in the Software without restriction, including without limitation
Anna Bridge 186:707f6e361f3e 13 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
Anna Bridge 186:707f6e361f3e 14 * and/or sell copies of the Software, and to permit persons to whom the
Anna Bridge 186:707f6e361f3e 15 * Software is furnished to do so, subject to the following conditions:
Anna Bridge 186:707f6e361f3e 16 *
Anna Bridge 186:707f6e361f3e 17 * The above copyright notice and this permission notice shall be included
Anna Bridge 186:707f6e361f3e 18 * in all copies or substantial portions of the Software.
Anna Bridge 186:707f6e361f3e 19 *
Anna Bridge 186:707f6e361f3e 20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
Anna Bridge 186:707f6e361f3e 21 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
Anna Bridge 186:707f6e361f3e 22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
Anna Bridge 186:707f6e361f3e 23 * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
Anna Bridge 186:707f6e361f3e 24 * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
Anna Bridge 186:707f6e361f3e 25 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
Anna Bridge 186:707f6e361f3e 26 * OTHER DEALINGS IN THE SOFTWARE.
Anna Bridge 186:707f6e361f3e 27 *
Anna Bridge 186:707f6e361f3e 28 * Except as contained in this notice, the name of Maxim Integrated
Anna Bridge 186:707f6e361f3e 29 * Products, Inc. shall not be used except as stated in the Maxim Integrated
Anna Bridge 186:707f6e361f3e 30 * Products, Inc. Branding Policy.
Anna Bridge 186:707f6e361f3e 31 *
Anna Bridge 186:707f6e361f3e 32 * The mere transfer of this software does not imply any licenses
Anna Bridge 186:707f6e361f3e 33 * of trade secrets, proprietary technology, copyrights, patents,
Anna Bridge 186:707f6e361f3e 34 * trademarks, maskwork rights, or any other form of intellectual
Anna Bridge 186:707f6e361f3e 35 * property whatsoever. Maxim Integrated Products, Inc. retains all
Anna Bridge 186:707f6e361f3e 36 * ownership rights.
Anna Bridge 186:707f6e361f3e 37 *
Anna Bridge 186:707f6e361f3e 38 * $Date: 2016-09-09 12:50:17 -0500 (Fri, 09 Sep 2016) $
Anna Bridge 186:707f6e361f3e 39 * $Revision: 24348 $
Anna Bridge 186:707f6e361f3e 40 *
Anna Bridge 186:707f6e361f3e 41 *************************************************************************** */
Anna Bridge 186:707f6e361f3e 42
Anna Bridge 186:707f6e361f3e 43 /* **** Includes **** */
Anna Bridge 186:707f6e361f3e 44 #include <string.h> /* Included for memcpy() & #includes stddef for NULL */
Anna Bridge 186:707f6e361f3e 45
Anna Bridge 186:707f6e361f3e 46 #include "mxc_config.h"
Anna Bridge 186:707f6e361f3e 47 #include "aes.h"
Anna Bridge 186:707f6e361f3e 48 #include "nvic_table.h"
Anna Bridge 186:707f6e361f3e 49
Anna Bridge 186:707f6e361f3e 50 /**
Anna Bridge 186:707f6e361f3e 51 * @ingroup aes
Anna Bridge 186:707f6e361f3e 52 * @{
Anna Bridge 186:707f6e361f3e 53 */
Anna Bridge 186:707f6e361f3e 54
Anna Bridge 186:707f6e361f3e 55 /* **** Definitions **** */
Anna Bridge 186:707f6e361f3e 56
Anna Bridge 186:707f6e361f3e 57 /* **** Globals **** */
Anna Bridge 186:707f6e361f3e 58
Anna Bridge 186:707f6e361f3e 59 /* **** Local Function Prototypes **** */
Anna Bridge 186:707f6e361f3e 60 static int aes_memcpy32(uint32_t *out, uint32_t *in, unsigned int count);
Anna Bridge 186:707f6e361f3e 61
Anna Bridge 186:707f6e361f3e 62 /* **** Functions **** */
Anna Bridge 186:707f6e361f3e 63
Anna Bridge 186:707f6e361f3e 64 /* ************************************************************************* */
Anna Bridge 186:707f6e361f3e 65 int AES_SetKey(const uint8_t *key, mxc_aes_mode_t mode)
Anna Bridge 186:707f6e361f3e 66 {
Anna Bridge 186:707f6e361f3e 67 unsigned int len;
Anna Bridge 186:707f6e361f3e 68
Anna Bridge 186:707f6e361f3e 69 /* Erase any existing key */
Anna Bridge 186:707f6e361f3e 70 MXC_AES_MEM->key[7] = MXC_AES_MEM->key[6] = MXC_AES_MEM->key[5] = MXC_AES_MEM->key[4] \
Anna Bridge 186:707f6e361f3e 71 = MXC_AES_MEM->key[3] = MXC_AES_MEM->key[2] = MXC_AES_MEM->key[1] = MXC_AES_MEM->key[0] \
Anna Bridge 186:707f6e361f3e 72 = 0x00000000;
Anna Bridge 186:707f6e361f3e 73
Anna Bridge 186:707f6e361f3e 74 /* Determine length of key */
Anna Bridge 186:707f6e361f3e 75 if (mode == MXC_E_AES_MODE_256) {
Anna Bridge 186:707f6e361f3e 76 len = MXC_AES_KEY_256_LEN;
Anna Bridge 186:707f6e361f3e 77 } else if (mode == MXC_E_AES_MODE_192) {
Anna Bridge 186:707f6e361f3e 78 len = MXC_AES_KEY_192_LEN;
Anna Bridge 186:707f6e361f3e 79 } else if (mode == MXC_E_AES_MODE_128) {
Anna Bridge 186:707f6e361f3e 80 len = MXC_AES_KEY_128_LEN;
Anna Bridge 186:707f6e361f3e 81 } else {
Anna Bridge 186:707f6e361f3e 82 return E_BAD_PARAM;
Anna Bridge 186:707f6e361f3e 83 }
Anna Bridge 186:707f6e361f3e 84
Anna Bridge 186:707f6e361f3e 85 /* Load new key, based on key mode */
Anna Bridge 186:707f6e361f3e 86 if (aes_memcpy32((uint32_t *)MXC_AES_MEM->key, (uint32_t *)key, len / sizeof(uint32_t)) < 0) {
Anna Bridge 186:707f6e361f3e 87 return E_NULL_PTR;
Anna Bridge 186:707f6e361f3e 88 }
Anna Bridge 186:707f6e361f3e 89
Anna Bridge 186:707f6e361f3e 90 return E_SUCCESS;
Anna Bridge 186:707f6e361f3e 91 }
Anna Bridge 186:707f6e361f3e 92
Anna Bridge 186:707f6e361f3e 93 /* ************************************************************************* */
Anna Bridge 186:707f6e361f3e 94 int AES_ECBOp(const uint8_t *in, uint8_t *out, mxc_aes_mode_t mode, mxc_aes_dir_t dir)
Anna Bridge 186:707f6e361f3e 95 {
Anna Bridge 186:707f6e361f3e 96 /* Output array can't be a NULL, unless we are in _ASYNC mode */
Anna Bridge 186:707f6e361f3e 97 if ((out == NULL)
Anna Bridge 186:707f6e361f3e 98 && ((dir != MXC_E_AES_ENCRYPT_ASYNC) && (dir != MXC_E_AES_DECRYPT_ASYNC))) {
Anna Bridge 186:707f6e361f3e 99 return E_NULL_PTR;
Anna Bridge 186:707f6e361f3e 100 }
Anna Bridge 186:707f6e361f3e 101
Anna Bridge 186:707f6e361f3e 102 /* Another encryption is already in progress */
Anna Bridge 186:707f6e361f3e 103 if (MXC_AES->ctrl & MXC_F_AES_CTRL_START) {
Anna Bridge 186:707f6e361f3e 104 return E_BUSY;
Anna Bridge 186:707f6e361f3e 105 }
Anna Bridge 186:707f6e361f3e 106
Anna Bridge 186:707f6e361f3e 107 /* Clear interrupt flag and any existing configuration*/
Anna Bridge 186:707f6e361f3e 108 MXC_AES->ctrl = MXC_F_AES_CTRL_INTFL;
Anna Bridge 186:707f6e361f3e 109
Anna Bridge 186:707f6e361f3e 110 /* Select key size & direction
Anna Bridge 186:707f6e361f3e 111 *
Anna Bridge 186:707f6e361f3e 112 * Note: This is done first to detect argument errors, before sensitive data
Anna Bridge 186:707f6e361f3e 113 * is loaded into AES_MEM block
Anna Bridge 186:707f6e361f3e 114 *
Anna Bridge 186:707f6e361f3e 115 */
Anna Bridge 186:707f6e361f3e 116 switch (mode) {
Anna Bridge 186:707f6e361f3e 117 case MXC_E_AES_MODE_128:
Anna Bridge 186:707f6e361f3e 118 MXC_AES->ctrl |= MXC_S_AES_CTRL_KEY_SIZE_128;
Anna Bridge 186:707f6e361f3e 119 break;
Anna Bridge 186:707f6e361f3e 120
Anna Bridge 186:707f6e361f3e 121 case MXC_E_AES_MODE_192:
Anna Bridge 186:707f6e361f3e 122 MXC_AES->ctrl |= MXC_S_AES_CTRL_KEY_SIZE_192;
Anna Bridge 186:707f6e361f3e 123 break;
Anna Bridge 186:707f6e361f3e 124
Anna Bridge 186:707f6e361f3e 125 case MXC_E_AES_MODE_256:
Anna Bridge 186:707f6e361f3e 126 MXC_AES->ctrl |= MXC_S_AES_CTRL_KEY_SIZE_256;
Anna Bridge 186:707f6e361f3e 127 break;
Anna Bridge 186:707f6e361f3e 128
Anna Bridge 186:707f6e361f3e 129 default:
Anna Bridge 186:707f6e361f3e 130 return E_BAD_PARAM;
Anna Bridge 186:707f6e361f3e 131 }
Anna Bridge 186:707f6e361f3e 132
Anna Bridge 186:707f6e361f3e 133 switch (dir) {
Anna Bridge 186:707f6e361f3e 134 case MXC_E_AES_ENCRYPT:
Anna Bridge 186:707f6e361f3e 135 case MXC_E_AES_ENCRYPT_ASYNC:
Anna Bridge 186:707f6e361f3e 136 MXC_AES->ctrl |= MXC_S_AES_CTRL_ENCRYPT_MODE;
Anna Bridge 186:707f6e361f3e 137 break;
Anna Bridge 186:707f6e361f3e 138
Anna Bridge 186:707f6e361f3e 139 case MXC_E_AES_DECRYPT:
Anna Bridge 186:707f6e361f3e 140 case MXC_E_AES_DECRYPT_ASYNC:
Anna Bridge 186:707f6e361f3e 141 MXC_AES->ctrl |= MXC_S_AES_CTRL_DECRYPT_MODE;
Anna Bridge 186:707f6e361f3e 142 break;
Anna Bridge 186:707f6e361f3e 143
Anna Bridge 186:707f6e361f3e 144 default:
Anna Bridge 186:707f6e361f3e 145 return E_BAD_PARAM;
Anna Bridge 186:707f6e361f3e 146 }
Anna Bridge 186:707f6e361f3e 147
Anna Bridge 186:707f6e361f3e 148 /* If non-blocking mode has been selected, interrupts are automatically enabled */
Anna Bridge 186:707f6e361f3e 149 if ((dir == MXC_E_AES_ENCRYPT_ASYNC) ||
Anna Bridge 186:707f6e361f3e 150 (dir == MXC_E_AES_DECRYPT_ASYNC)) {
Anna Bridge 186:707f6e361f3e 151 MXC_AES->ctrl |= MXC_F_AES_CTRL_INTEN;
Anna Bridge 186:707f6e361f3e 152 }
Anna Bridge 186:707f6e361f3e 153
Anna Bridge 186:707f6e361f3e 154 /* Load input into engine */
Anna Bridge 186:707f6e361f3e 155 if (aes_memcpy32((uint32_t *)MXC_AES_MEM->inp, (uint32_t *)in, MXC_AES_DATA_LEN / sizeof(uint32_t)) < 0) {
Anna Bridge 186:707f6e361f3e 156 return E_NULL_PTR;
Anna Bridge 186:707f6e361f3e 157 }
Anna Bridge 186:707f6e361f3e 158
Anna Bridge 186:707f6e361f3e 159 /* Start operation */
Anna Bridge 186:707f6e361f3e 160 MXC_AES->ctrl |= MXC_F_AES_CTRL_START;
Anna Bridge 186:707f6e361f3e 161
Anna Bridge 186:707f6e361f3e 162 /* Block, waiting on engine to complete, or fall through if non-blocking */
Anna Bridge 186:707f6e361f3e 163 if ((dir != MXC_E_AES_ENCRYPT_ASYNC) &&
Anna Bridge 186:707f6e361f3e 164 (dir != MXC_E_AES_DECRYPT_ASYNC)) {
Anna Bridge 186:707f6e361f3e 165 while (MXC_AES->ctrl & MXC_F_AES_CTRL_START) {
Anna Bridge 186:707f6e361f3e 166 /* Ensure that this wait loop is not optimized out */
Anna Bridge 186:707f6e361f3e 167 __NOP();
Anna Bridge 186:707f6e361f3e 168 }
Anna Bridge 186:707f6e361f3e 169
Anna Bridge 186:707f6e361f3e 170 /* Get output from engine */
Anna Bridge 186:707f6e361f3e 171 return AES_GetOutput(out);
Anna Bridge 186:707f6e361f3e 172 }
Anna Bridge 186:707f6e361f3e 173
Anna Bridge 186:707f6e361f3e 174 return E_SUCCESS;
Anna Bridge 186:707f6e361f3e 175 }
Anna Bridge 186:707f6e361f3e 176
Anna Bridge 186:707f6e361f3e 177 /* ************************************************************************* */
Anna Bridge 186:707f6e361f3e 178 int AES_GetOutput(uint8_t *out)
Anna Bridge 186:707f6e361f3e 179 {
Anna Bridge 186:707f6e361f3e 180 /* Don't read it out of the AES memory unless engine is idle */
Anna Bridge 186:707f6e361f3e 181 if (MXC_AES->ctrl & MXC_F_AES_CTRL_START) {
Anna Bridge 186:707f6e361f3e 182 return E_BUSY;
Anna Bridge 186:707f6e361f3e 183 }
Anna Bridge 186:707f6e361f3e 184
Anna Bridge 186:707f6e361f3e 185 /* Pull out result */
Anna Bridge 186:707f6e361f3e 186 if (aes_memcpy32((uint32_t *)out, (uint32_t *)MXC_AES_MEM->out, MXC_AES_DATA_LEN / sizeof(uint32_t)) < 0) {
Anna Bridge 186:707f6e361f3e 187 return E_NULL_PTR;
Anna Bridge 186:707f6e361f3e 188 }
Anna Bridge 186:707f6e361f3e 189
Anna Bridge 186:707f6e361f3e 190 /* Clear interrupt flag, write 1 to clear */
Anna Bridge 186:707f6e361f3e 191 MXC_AES->ctrl |= MXC_F_AES_CTRL_INTFL;
Anna Bridge 186:707f6e361f3e 192
Anna Bridge 186:707f6e361f3e 193 return E_SUCCESS;
Anna Bridge 186:707f6e361f3e 194 }
Anna Bridge 186:707f6e361f3e 195
Anna Bridge 186:707f6e361f3e 196 /**
Anna Bridge 186:707f6e361f3e 197 * @internal This memory copy is used only by the AES module to avoid data leakage by the standard C library.
Anna Bridge 186:707f6e361f3e 198 * Copy count number of 32-bit locations from in to out
Anna Bridge 186:707f6e361f3e 199 */
Anna Bridge 186:707f6e361f3e 200 static int aes_memcpy32(uint32_t *out, uint32_t *in, unsigned int count)
Anna Bridge 186:707f6e361f3e 201 {
Anna Bridge 186:707f6e361f3e 202 if ((out == NULL) || (in == NULL)) {
Anna Bridge 186:707f6e361f3e 203 /* Invalid arguments, but is internal-only so don't use error codes */
Anna Bridge 186:707f6e361f3e 204 return -1;
Anna Bridge 186:707f6e361f3e 205 }
Anna Bridge 186:707f6e361f3e 206
Anna Bridge 186:707f6e361f3e 207 while (count--) {
Anna Bridge 186:707f6e361f3e 208 *out++ = *in++;
Anna Bridge 186:707f6e361f3e 209 }
Anna Bridge 186:707f6e361f3e 210
Anna Bridge 186:707f6e361f3e 211 return 0;
Anna Bridge 186:707f6e361f3e 212 }
Anna Bridge 186:707f6e361f3e 213
Anna Bridge 186:707f6e361f3e 214 /**@} end of group aes */