/***************************************************************************//** | |
* @file em_aes.h | |
* @brief Advanced encryption standard (AES) accelerator peripheral API. | |
* @version 5.1.2 | |
******************************************************************************* | |
* @section License | |
* <b>Copyright 2016 Silicon Laboratories, Inc. http://www.silabs.com</b> | |
******************************************************************************* | |
* | |
* Permission is granted to anyone to use this software for any purpose, | |
* including commercial applications, and to alter it and redistribute it | |
* freely, subject to the following restrictions: | |
* | |
* 1. The origin of this software must not be misrepresented; you must not | |
* claim that you wrote the original software. | |
* 2. Altered source versions must be plainly marked as such, and must not be | |
* misrepresented as being the original software. | |
* 3. This notice may not be removed or altered from any source distribution. | |
* | |
* DISCLAIMER OF WARRANTY/LIMITATION OF REMEDIES: Silicon Labs has no | |
* obligation to support this Software. Silicon Labs is providing the | |
* Software "AS IS", with no express or implied warranties of any kind, | |
* including, but not limited to, any implied warranties of merchantability | |
* or fitness for any particular purpose or warranties against infringement | |
* of any proprietary rights of a third party. | |
* | |
* Silicon Labs will not be liable for any consequential, incidental, or | |
* special damages, or any other relief, or for any claim by any third party, | |
* arising from your use of this Software. | |
* | |
******************************************************************************/ | |
#ifndef EM_AES_H | |
#define EM_AES_H | |
#include "em_device.h" | |
#if defined(AES_COUNT) && (AES_COUNT > 0) | |
#include <stdbool.h> | |
#ifdef __cplusplus | |
extern "C" { | |
#endif | |
/***************************************************************************//** | |
* @addtogroup emlib | |
* @{ | |
******************************************************************************/ | |
/***************************************************************************//** | |
* @addtogroup AES | |
* @brief Advanced Encryption Standard Accelerator (AES) Peripheral API. | |
* | |
* @details | |
* The AES peripheral supports AES block cipher encryption and decryption with | |
* 128 bit and 256 bit keys. The following block cipher modes are supported: | |
* @li CBC - Cipher Block Chaining mode | |
* @li CFB - Cipher Feedback mode | |
* @li CTR - Counter mode | |
* @li ECB - Electronic Code Book mode | |
* @li OFB - Output Feedback mode | |
* | |
* The following input/output notations should be noted: | |
* | |
* @li Input/output data (plaintext, ciphertext, key etc) are treated as | |
* byte arrays, starting with most significant byte. Ie, 32 bytes of | |
* plaintext (B0...B31) is located in memory in the same order, with B0 at | |
* the lower address and B31 at the higher address. | |
* | |
* @li Byte arrays must always be a multiple of AES block size, ie a multiple | |
* of 16. Padding, if required, is done at the end of the byte array. | |
* | |
* @li Byte arrays should be word (32 bit) aligned for performance | |
* considerations, since the array is accessed with 32 bit access type. | |
* The Cortex-M supports unaligned accesses, but with a performance penalty. | |
* | |
* @li It is possible to specify the same output buffer as input buffer | |
* as long as they point to the same address. In that case the provided input | |
* buffer is replaced with the encrypted/decrypted output. Notice that the | |
* buffers must be exactly overlapping. If partly overlapping, the | |
* behaviour is undefined. | |
* | |
* It is up to the user to use a cipher mode according to its requirements | |
* in order to not break security. Please refer to specific cipher mode | |
* theory for details. | |
* | |
* References: | |
* @li Wikipedia - Cipher modes, http://en.wikipedia.org/wiki/Cipher_modes | |
* | |
* @li Recommendation for Block Cipher Modes of Operation, | |
* NIST Special Publication 800-38A, 2001 Edition, | |
* http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf | |
* | |
* E.g. the following example shows how to perform an AES-128 CBC encryption: | |
* | |
* Enable clocks: | |
* @include em_aes_clock_enable.c | |
* | |
* Execute AES-128 CBC encryption: | |
* @include em_aes_basic_usage.c | |
* | |
* @{ | |
******************************************************************************/ | |
/******************************************************************************* | |
****************************** TYPEDEFS *********************************** | |
******************************************************************************/ | |
/** | |
* @brief | |
* AES counter modification function pointer. | |
* @details | |
* Parameters: | |
* @li ctr - Ptr to byte array (16 bytes) holding counter to be modified. | |
*/ | |
typedef void (*AES_CtrFuncPtr_TypeDef)(uint8_t *ctr); | |
/******************************************************************************* | |
***************************** PROTOTYPES ********************************** | |
******************************************************************************/ | |
void AES_CBC128(uint8_t *out, | |
const uint8_t *in, | |
unsigned int len, | |
const uint8_t *key, | |
const uint8_t *iv, | |
bool encrypt); | |
#if defined( AES_CTRL_AES256 ) | |
void AES_CBC256(uint8_t *out, | |
const uint8_t *in, | |
unsigned int len, | |
const uint8_t *key, | |
const uint8_t *iv, | |
bool encrypt); | |
#endif | |
void AES_CFB128(uint8_t *out, | |
const uint8_t *in, | |
unsigned int len, | |
const uint8_t *key, | |
const uint8_t *iv, | |
bool encrypt); | |
#if defined( AES_CTRL_AES256 ) | |
void AES_CFB256(uint8_t *out, | |
const uint8_t *in, | |
unsigned int len, | |
const uint8_t *key, | |
const uint8_t *iv, | |
bool encrypt); | |
#endif | |
void AES_CTR128(uint8_t *out, | |
const uint8_t *in, | |
unsigned int len, | |
const uint8_t *key, | |
uint8_t *ctr, | |
AES_CtrFuncPtr_TypeDef ctrFunc); | |
#if defined( AES_CTRL_AES256 ) | |
void AES_CTR256(uint8_t *out, | |
const uint8_t *in, | |
unsigned int len, | |
const uint8_t *key, | |
uint8_t *ctr, | |
AES_CtrFuncPtr_TypeDef ctrFunc); | |
#endif | |
void AES_CTRUpdate32Bit(uint8_t *ctr); | |
void AES_DecryptKey128(uint8_t *out, const uint8_t *in); | |
#if defined( AES_CTRL_AES256 ) | |
void AES_DecryptKey256(uint8_t *out, const uint8_t *in); | |
#endif | |
void AES_ECB128(uint8_t *out, | |
const uint8_t *in, | |
unsigned int len, | |
const uint8_t *key, | |
bool encrypt); | |
#if defined( AES_CTRL_AES256 ) | |
void AES_ECB256(uint8_t *out, | |
const uint8_t *in, | |
unsigned int len, | |
const uint8_t *key, | |
bool encrypt); | |
#endif | |
/***************************************************************************//** | |
* @brief | |
* Clear one or more pending AES interrupts. | |
* | |
* @param[in] flags | |
* Pending AES interrupt source to clear. Use a bitwise logic OR combination of | |
* valid interrupt flags for the AES module (AES_IF_nnn). | |
******************************************************************************/ | |
__STATIC_INLINE void AES_IntClear(uint32_t flags) | |
{ | |
AES->IFC = flags; | |
} | |
/***************************************************************************//** | |
* @brief | |
* Disable one or more AES interrupts. | |
* | |
* @param[in] flags | |
* AES interrupt sources to disable. Use a bitwise logic OR combination of | |
* valid interrupt flags for the AES module (AES_IF_nnn). | |
******************************************************************************/ | |
__STATIC_INLINE void AES_IntDisable(uint32_t flags) | |
{ | |
AES->IEN &= ~(flags); | |
} | |
/***************************************************************************//** | |
* @brief | |
* Enable one or more AES interrupts. | |
* | |
* @note | |
* Depending on the use, a pending interrupt may already be set prior to | |
* enabling the interrupt. Consider using AES_IntClear() prior to enabling | |
* if such a pending interrupt should be ignored. | |
* | |
* @param[in] flags | |
* AES interrupt sources to enable. Use a bitwise logic OR combination of | |
* valid interrupt flags for the AES module (AES_IF_nnn). | |
******************************************************************************/ | |
__STATIC_INLINE void AES_IntEnable(uint32_t flags) | |
{ | |
AES->IEN |= flags; | |
} | |
/***************************************************************************//** | |
* @brief | |
* Get pending AES interrupt flags. | |
* | |
* @note | |
* The event bits are not cleared by the use of this function. | |
* | |
* @return | |
* AES interrupt sources pending. A bitwise logic OR combination of valid | |
* interrupt flags for the AES module (AES_IF_nnn). | |
******************************************************************************/ | |
__STATIC_INLINE uint32_t AES_IntGet(void) | |
{ | |
return AES->IF; | |
} | |
/***************************************************************************//** | |
* @brief | |
* Get enabled and pending AES interrupt flags. | |
* Useful for handling more interrupt sources in the same interrupt handler. | |
* | |
* @note | |
* Interrupt flags are not cleared by the use of this function. | |
* | |
* @return | |
* Pending and enabled AES interrupt sources | |
* The return value is the bitwise AND of | |
* - the enabled interrupt sources in AES_IEN and | |
* - the pending interrupt flags AES_IF | |
******************************************************************************/ | |
__STATIC_INLINE uint32_t AES_IntGetEnabled(void) | |
{ | |
uint32_t ien; | |
ien = AES->IEN; | |
return AES->IF & ien; | |
} | |
/***************************************************************************//** | |
* @brief | |
* Set one or more pending AES interrupts from SW. | |
* | |
* @param[in] flags | |
* AES interrupt sources to set to pending. Use a bitwise logic OR combination | |
* of valid interrupt flags for the AES module (AES_IF_nnn). | |
******************************************************************************/ | |
__STATIC_INLINE void AES_IntSet(uint32_t flags) | |
{ | |
AES->IFS = flags; | |
} | |
void AES_OFB128(uint8_t *out, | |
const uint8_t *in, | |
unsigned int len, | |
const uint8_t *key, | |
const uint8_t *iv); | |
#if defined( AES_CTRL_AES256 ) | |
void AES_OFB256(uint8_t *out, | |
const uint8_t *in, | |
unsigned int len, | |
const uint8_t *key, | |
const uint8_t *iv); | |
#endif | |
/** @} (end addtogroup AES) */ | |
/** @} (end addtogroup emlib) */ | |
#ifdef __cplusplus | |
} | |
#endif | |
#endif /* defined(AES_COUNT) && (AES_COUNT > 0) */ | |
#endif /* EM_AES_H */ | |