aes.h

00001 /**
00002  * \file aes.h
00003  *
00004  * \brief AES block cipher
00005  *
00006  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
00007  *  SPDX-License-Identifier: Apache-2.0
00008  *
00009  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
00010  *  not use this file except in compliance with the License.
00011  *  You may obtain a copy of the License at
00012  *
00013  *  http://www.apache.org/licenses/LICENSE-2.0
00014  *
00015  *  Unless required by applicable law or agreed to in writing, software
00016  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00017  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00018  *  See the License for the specific language governing permissions and
00019  *  limitations under the License.
00020  *
00021  *  This file is part of mbed TLS (https://tls.mbed.org)
00022  */
00023 #ifndef MBEDTLS_AES_H
00024 #define MBEDTLS_AES_H
00025 
00026 #if !defined(MBEDTLS_CONFIG_FILE)
00027 #include "config.h"
00028 #else
00029 #include MBEDTLS_CONFIG_FILE
00030 #endif
00031 
00032 #include <stddef.h>
00033 #include <stdint.h>
00034 
00035 /* padlock.c and aesni.c rely on these values! */
00036 #define MBEDTLS_AES_ENCRYPT     1
00037 #define MBEDTLS_AES_DECRYPT     0
00038 
00039 #define MBEDTLS_ERR_AES_INVALID_KEY_LENGTH                -0x0020  /**< Invalid key length. */
00040 #define MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH              -0x0022  /**< Invalid data input length. */
00041 
00042 #if !defined(MBEDTLS_AES_ALT)
00043 // Regular implementation
00044 //
00045 
00046 #ifdef __cplusplus
00047 extern "C" {
00048 #endif
00049 
00050 /**
00051  * \brief          AES context structure
00052  *
00053  * \note           buf is able to hold 32 extra bytes, which can be used:
00054  *                 - for alignment purposes if VIA padlock is used, and/or
00055  *                 - to simplify key expansion in the 256-bit case by
00056  *                 generating an extra round key
00057  */
00058 typedef struct
00059 {
00060     int nr ;                     /*!<  number of rounds  */
00061     uint32_t *rk ;               /*!<  AES round keys    */
00062     uint32_t buf[68];           /*!<  unaligned data    */
00063 }
00064 mbedtls_aes_context;
00065 
00066 /**
00067  * \brief          Initialize AES context
00068  *
00069  * \param ctx      AES context to be initialized
00070  */
00071 void mbedtls_aes_init( mbedtls_aes_context *ctx );
00072 
00073 /**
00074  * \brief          Clear AES context
00075  *
00076  * \param ctx      AES context to be cleared
00077  */
00078 void mbedtls_aes_free( mbedtls_aes_context *ctx );
00079 
00080 /**
00081  * \brief          AES key schedule (encryption)
00082  *
00083  * \param ctx      AES context to be initialized
00084  * \param key      encryption key
00085  * \param keybits  must be 128, 192 or 256
00086  *
00087  * \return         0 if successful, or MBEDTLS_ERR_AES_INVALID_KEY_LENGTH
00088  */
00089 int mbedtls_aes_setkey_enc( mbedtls_aes_context *ctx, const unsigned char *key,
00090                     unsigned int keybits );
00091 
00092 /**
00093  * \brief          AES key schedule (decryption)
00094  *
00095  * \param ctx      AES context to be initialized
00096  * \param key      decryption key
00097  * \param keybits  must be 128, 192 or 256
00098  *
00099  * \return         0 if successful, or MBEDTLS_ERR_AES_INVALID_KEY_LENGTH
00100  */
00101 int mbedtls_aes_setkey_dec( mbedtls_aes_context *ctx, const unsigned char *key,
00102                     unsigned int keybits );
00103 
00104 /**
00105  * \brief          AES-ECB block encryption/decryption
00106  *
00107  * \param ctx      AES context
00108  * \param mode     MBEDTLS_AES_ENCRYPT or MBEDTLS_AES_DECRYPT
00109  * \param input    16-byte input block
00110  * \param output   16-byte output block
00111  *
00112  * \return         0 if successful
00113  */
00114 int mbedtls_aes_crypt_ecb( mbedtls_aes_context *ctx,
00115                     int mode,
00116                     const unsigned char input[16],
00117                     unsigned char output[16] );
00118 
00119 #if defined(MBEDTLS_CIPHER_MODE_CBC)
00120 /**
00121  * \brief          AES-CBC buffer encryption/decryption
00122  *                 Length should be a multiple of the block
00123  *                 size (16 bytes)
00124  *
00125  * \note           Upon exit, the content of the IV is updated so that you can
00126  *                 call the function same function again on the following
00127  *                 block(s) of data and get the same result as if it was
00128  *                 encrypted in one call. This allows a "streaming" usage.
00129  *                 If on the other hand you need to retain the contents of the
00130  *                 IV, you should either save it manually or use the cipher
00131  *                 module instead.
00132  *
00133  * \param ctx      AES context
00134  * \param mode     MBEDTLS_AES_ENCRYPT or MBEDTLS_AES_DECRYPT
00135  * \param length   length of the input data
00136  * \param iv       initialization vector (updated after use)
00137  * \param input    buffer holding the input data
00138  * \param output   buffer holding the output data
00139  *
00140  * \return         0 if successful, or MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH
00141  */
00142 int mbedtls_aes_crypt_cbc( mbedtls_aes_context *ctx,
00143                     int mode,
00144                     size_t length,
00145                     unsigned char iv[16],
00146                     const unsigned char *input,
00147                     unsigned char *output );
00148 #endif /* MBEDTLS_CIPHER_MODE_CBC */
00149 
00150 #if defined(MBEDTLS_CIPHER_MODE_CFB)
00151 /**
00152  * \brief          AES-CFB128 buffer encryption/decryption.
00153  *
00154  * Note: Due to the nature of CFB you should use the same key schedule for
00155  * both encryption and decryption. So a context initialized with
00156  * mbedtls_aes_setkey_enc() for both MBEDTLS_AES_ENCRYPT and MBEDTLS_AES_DECRYPT.
00157  *
00158  * \note           Upon exit, the content of the IV is updated so that you can
00159  *                 call the function same function again on the following
00160  *                 block(s) of data and get the same result as if it was
00161  *                 encrypted in one call. This allows a "streaming" usage.
00162  *                 If on the other hand you need to retain the contents of the
00163  *                 IV, you should either save it manually or use the cipher
00164  *                 module instead.
00165  *
00166  * \param ctx      AES context
00167  * \param mode     MBEDTLS_AES_ENCRYPT or MBEDTLS_AES_DECRYPT
00168  * \param length   length of the input data
00169  * \param iv_off   offset in IV (updated after use)
00170  * \param iv       initialization vector (updated after use)
00171  * \param input    buffer holding the input data
00172  * \param output   buffer holding the output data
00173  *
00174  * \return         0 if successful
00175  */
00176 int mbedtls_aes_crypt_cfb128( mbedtls_aes_context *ctx,
00177                        int mode,
00178                        size_t length,
00179                        size_t *iv_off,
00180                        unsigned char iv[16],
00181                        const unsigned char *input,
00182                        unsigned char *output );
00183 
00184 /**
00185  * \brief          AES-CFB8 buffer encryption/decryption.
00186  *
00187  * Note: Due to the nature of CFB you should use the same key schedule for
00188  * both encryption and decryption. So a context initialized with
00189  * mbedtls_aes_setkey_enc() for both MBEDTLS_AES_ENCRYPT and MBEDTLS_AES_DECRYPT.
00190  *
00191  * \note           Upon exit, the content of the IV is updated so that you can
00192  *                 call the function same function again on the following
00193  *                 block(s) of data and get the same result as if it was
00194  *                 encrypted in one call. This allows a "streaming" usage.
00195  *                 If on the other hand you need to retain the contents of the
00196  *                 IV, you should either save it manually or use the cipher
00197  *                 module instead.
00198  *
00199  * \param ctx      AES context
00200  * \param mode     MBEDTLS_AES_ENCRYPT or MBEDTLS_AES_DECRYPT
00201  * \param length   length of the input data
00202  * \param iv       initialization vector (updated after use)
00203  * \param input    buffer holding the input data
00204  * \param output   buffer holding the output data
00205  *
00206  * \return         0 if successful
00207  */
00208 int mbedtls_aes_crypt_cfb8( mbedtls_aes_context *ctx,
00209                     int mode,
00210                     size_t length,
00211                     unsigned char iv[16],
00212                     const unsigned char *input,
00213                     unsigned char *output );
00214 #endif /*MBEDTLS_CIPHER_MODE_CFB */
00215 
00216 #if defined(MBEDTLS_CIPHER_MODE_CTR)
00217 /**
00218  * \brief               AES-CTR buffer encryption/decryption
00219  *
00220  * Warning: You have to keep the maximum use of your counter in mind!
00221  *
00222  * Note: Due to the nature of CTR you should use the same key schedule for
00223  * both encryption and decryption. So a context initialized with
00224  * mbedtls_aes_setkey_enc() for both MBEDTLS_AES_ENCRYPT and MBEDTLS_AES_DECRYPT.
00225  *
00226  * \param ctx           AES context
00227  * \param length        The length of the data
00228  * \param nc_off        The offset in the current stream_block (for resuming
00229  *                      within current cipher stream). The offset pointer to
00230  *                      should be 0 at the start of a stream.
00231  * \param nonce_counter The 128-bit nonce and counter.
00232  * \param stream_block  The saved stream-block for resuming. Is overwritten
00233  *                      by the function.
00234  * \param input         The input data stream
00235  * \param output        The output data stream
00236  *
00237  * \return         0 if successful
00238  */
00239 int mbedtls_aes_crypt_ctr( mbedtls_aes_context *ctx,
00240                        size_t length,
00241                        size_t *nc_off,
00242                        unsigned char nonce_counter[16],
00243                        unsigned char stream_block[16],
00244                        const unsigned char *input,
00245                        unsigned char *output );
00246 #endif /* MBEDTLS_CIPHER_MODE_CTR */
00247 
00248 /**
00249  * \brief           Internal AES block encryption function
00250  *                  (Only exposed to allow overriding it,
00251  *                  see MBEDTLS_AES_ENCRYPT_ALT)
00252  *
00253  * \param ctx       AES context
00254  * \param input     Plaintext block
00255  * \param output    Output (ciphertext) block
00256  */
00257 void mbedtls_aes_encrypt( mbedtls_aes_context *ctx,
00258                           const unsigned char input[16],
00259                           unsigned char output[16] );
00260 
00261 /**
00262  * \brief           Internal AES block decryption function
00263  *                  (Only exposed to allow overriding it,
00264  *                  see MBEDTLS_AES_DECRYPT_ALT)
00265  *
00266  * \param ctx       AES context
00267  * \param input     Ciphertext block
00268  * \param output    Output (plaintext) block
00269  */
00270 void mbedtls_aes_decrypt( mbedtls_aes_context *ctx,
00271                           const unsigned char input[16],
00272                           unsigned char output[16] );
00273 
00274 #ifdef __cplusplus
00275 }
00276 #endif
00277 
00278 #else  /* MBEDTLS_AES_ALT */
00279 #include "aes_alt.h"
00280 #endif /* MBEDTLS_AES_ALT */
00281 
00282 #ifdef __cplusplus
00283 extern "C" {
00284 #endif
00285 
00286 /**
00287  * \brief          Checkup routine
00288  *
00289  * \return         0 if successful, or 1 if the test failed
00290  */
00291 int mbedtls_aes_self_test( int verbose );
00292 
00293 #ifdef __cplusplus
00294 }
00295 #endif
00296 
00297 #endif /* aes.h */