blowfish.h

00001 /**
00002  * \file blowfish.h
00003  *
00004  * \brief Blowfish block cipher
00005  */
00006 /*
00007  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
00008  *  SPDX-License-Identifier: Apache-2.0
00009  *
00010  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
00011  *  not use this file except in compliance with the License.
00012  *  You may obtain a copy of the License at
00013  *
00014  *  http://www.apache.org/licenses/LICENSE-2.0
00015  *
00016  *  Unless required by applicable law or agreed to in writing, software
00017  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00018  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00019  *  See the License for the specific language governing permissions and
00020  *  limitations under the License.
00021  *
00022  *  This file is part of mbed TLS (https://tls.mbed.org)
00023  */
00024 #ifndef MBEDTLS_BLOWFISH_H
00025 #define MBEDTLS_BLOWFISH_H
00026 
00027 #if !defined(MBEDTLS_CONFIG_FILE)
00028 #include "mbedtls/config.h"
00029 #else
00030 #include MBEDTLS_CONFIG_FILE
00031 #endif
00032 
00033 #include <stddef.h>
00034 #include <stdint.h>
00035 
00036 #include "mbedtls/platform_util.h"
00037 
00038 #define MBEDTLS_BLOWFISH_ENCRYPT     1
00039 #define MBEDTLS_BLOWFISH_DECRYPT     0
00040 #define MBEDTLS_BLOWFISH_MAX_KEY_BITS     448
00041 #define MBEDTLS_BLOWFISH_MIN_KEY_BITS     32
00042 #define MBEDTLS_BLOWFISH_ROUNDS      16         /**< Rounds to use. When increasing this value, make sure to extend the initialisation vectors */
00043 #define MBEDTLS_BLOWFISH_BLOCKSIZE   8          /* Blowfish uses 64 bit blocks */
00044 
00045 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
00046 #define MBEDTLS_ERR_BLOWFISH_INVALID_KEY_LENGTH   MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( -0x0016 )
00047 #endif /* !MBEDTLS_DEPRECATED_REMOVED */
00048 #define MBEDTLS_ERR_BLOWFISH_BAD_INPUT_DATA -0x0016 /**< Bad input data. */
00049 
00050 #define MBEDTLS_ERR_BLOWFISH_INVALID_INPUT_LENGTH -0x0018 /**< Invalid data input length. */
00051 
00052 /* MBEDTLS_ERR_BLOWFISH_HW_ACCEL_FAILED is deprecated and should not be used.
00053  */
00054 #define MBEDTLS_ERR_BLOWFISH_HW_ACCEL_FAILED                   -0x0017  /**< Blowfish hardware accelerator failed. */
00055 
00056 #ifdef __cplusplus
00057 extern "C" {
00058 #endif
00059 
00060 #if !defined(MBEDTLS_BLOWFISH_ALT)
00061 // Regular implementation
00062 //
00063 
00064 /**
00065  * \brief          Blowfish context structure
00066  */
00067 typedef struct mbedtls_blowfish_context
00068 {
00069     uint32_t P [MBEDTLS_BLOWFISH_ROUNDS + 2];    /*!<  Blowfish round keys    */
00070     uint32_t S [4][256];                 /*!<  key dependent S-boxes  */
00071 }
00072 mbedtls_blowfish_context;
00073 
00074 #else  /* MBEDTLS_BLOWFISH_ALT */
00075 #include "blowfish_alt.h"
00076 #endif /* MBEDTLS_BLOWFISH_ALT */
00077 
00078 /**
00079  * \brief          Initialize a Blowfish context.
00080  *
00081  * \param ctx      The Blowfish context to be initialized.
00082  *                 This must not be \c NULL.
00083  */
00084 void mbedtls_blowfish_init( mbedtls_blowfish_context *ctx );
00085 
00086 /**
00087  * \brief          Clear a Blowfish context.
00088  *
00089  * \param ctx      The Blowfish context to be cleared.
00090  *                 This may be \c NULL, in which case this function
00091  *                 returns immediately. If it is not \c NULL, it must
00092  *                 point to an initialized Blowfish context.
00093  */
00094 void mbedtls_blowfish_free( mbedtls_blowfish_context *ctx );
00095 
00096 /**
00097  * \brief          Perform a Blowfish key schedule operation.
00098  *
00099  * \param ctx      The Blowfish context to perform the key schedule on.
00100  * \param key      The encryption key. This must be a readable buffer of
00101  *                 length \p keybits Bits.
00102  * \param keybits  The length of \p key in Bits. This must be between
00103  *                 \c 32 and \c 448 and a multiple of \c 8.
00104  *
00105  * \return         \c 0 if successful.
00106  * \return         A negative error code on failure.
00107  */
00108 int mbedtls_blowfish_setkey( mbedtls_blowfish_context *ctx, const unsigned char *key,
00109                      unsigned int keybits );
00110 
00111 /**
00112  * \brief          Perform a Blowfish-ECB block encryption/decryption operation.
00113  *
00114  * \param ctx      The Blowfish context to use. This must be initialized
00115  *                 and bound to a key.
00116  * \param mode     The mode of operation. Possible values are
00117  *                 #MBEDTLS_BLOWFISH_ENCRYPT for encryption, or
00118  *                 #MBEDTLS_BLOWFISH_DECRYPT for decryption.
00119  * \param input    The input block. This must be a readable buffer
00120  *                 of size \c 8 Bytes.
00121  * \param output   The output block. This must be a writable buffer
00122  *                 of size \c 8 Bytes.
00123  *
00124  * \return         \c 0 if successful.
00125  * \return         A negative error code on failure.
00126  */
00127 int mbedtls_blowfish_crypt_ecb( mbedtls_blowfish_context *ctx,
00128                         int mode,
00129                         const unsigned char input[MBEDTLS_BLOWFISH_BLOCKSIZE],
00130                         unsigned char output[MBEDTLS_BLOWFISH_BLOCKSIZE] );
00131 
00132 #if defined(MBEDTLS_CIPHER_MODE_CBC)
00133 /**
00134  * \brief          Perform a Blowfish-CBC buffer encryption/decryption operation.
00135  *
00136  * \note           Upon exit, the content of the IV is updated so that you can
00137  *                 call the function same function again on the following
00138  *                 block(s) of data and get the same result as if it was
00139  *                 encrypted in one call. This allows a "streaming" usage.
00140  *                 If on the other hand you need to retain the contents of the
00141  *                 IV, you should either save it manually or use the cipher
00142  *                 module instead.
00143  *
00144  * \param ctx      The Blowfish context to use. This must be initialized
00145  *                 and bound to a key.
00146  * \param mode     The mode of operation. Possible values are
00147  *                 #MBEDTLS_BLOWFISH_ENCRYPT for encryption, or
00148  *                 #MBEDTLS_BLOWFISH_DECRYPT for decryption.
00149  * \param length   The length of the input data in Bytes. This must be
00150  *                 multiple of \c 8.
00151  * \param iv       The initialization vector. This must be a read/write buffer
00152  *                 of length \c 8 Bytes. It is updated by this function.
00153  * \param input    The input data. This must be a readable buffer of length
00154  *                 \p length Bytes.
00155  * \param output   The output data. This must be a writable buffer of length
00156  *                 \p length Bytes.
00157  *
00158  * \return         \c 0 if successful.
00159  * \return         A negative error code on failure.
00160  */
00161 int mbedtls_blowfish_crypt_cbc( mbedtls_blowfish_context *ctx,
00162                         int mode,
00163                         size_t length,
00164                         unsigned char iv[MBEDTLS_BLOWFISH_BLOCKSIZE],
00165                         const unsigned char *input,
00166                         unsigned char *output );
00167 #endif /* MBEDTLS_CIPHER_MODE_CBC */
00168 
00169 #if defined(MBEDTLS_CIPHER_MODE_CFB)
00170 /**
00171  * \brief          Perform a Blowfish CFB buffer encryption/decryption operation.
00172  *
00173  * \note           Upon exit, the content of the IV is updated so that you can
00174  *                 call the function same function again on the following
00175  *                 block(s) of data and get the same result as if it was
00176  *                 encrypted in one call. This allows a "streaming" usage.
00177  *                 If on the other hand you need to retain the contents of the
00178  *                 IV, you should either save it manually or use the cipher
00179  *                 module instead.
00180  *
00181  * \param ctx      The Blowfish context to use. This must be initialized
00182  *                 and bound to a key.
00183  * \param mode     The mode of operation. Possible values are
00184  *                 #MBEDTLS_BLOWFISH_ENCRYPT for encryption, or
00185  *                 #MBEDTLS_BLOWFISH_DECRYPT for decryption.
00186  * \param length   The length of the input data in Bytes.
00187  * \param iv_off   The offset in the initialiation vector.
00188  *                 The value pointed to must be smaller than \c 8 Bytes.
00189  *                 It is updated by this function to support the aforementioned
00190  *                 streaming usage.
00191  * \param iv       The initialization vector. This must be a read/write buffer
00192  *                 of size \c 8 Bytes. It is updated after use.
00193  * \param input    The input data. This must be a readable buffer of length
00194  *                 \p length Bytes.
00195  * \param output   The output data. This must be a writable buffer of length
00196  *                 \p length Bytes.
00197  *
00198  * \return         \c 0 if successful.
00199  * \return         A negative error code on failure.
00200  */
00201 int mbedtls_blowfish_crypt_cfb64( mbedtls_blowfish_context *ctx,
00202                           int mode,
00203                           size_t length,
00204                           size_t *iv_off,
00205                           unsigned char iv[MBEDTLS_BLOWFISH_BLOCKSIZE],
00206                           const unsigned char *input,
00207                           unsigned char *output );
00208 #endif /*MBEDTLS_CIPHER_MODE_CFB */
00209 
00210 #if defined(MBEDTLS_CIPHER_MODE_CTR)
00211 /**
00212  * \brief      Perform a Blowfish-CTR buffer encryption/decryption operation.
00213  *
00214  * \warning    You must never reuse a nonce value with the same key. Doing so
00215  *             would void the encryption for the two messages encrypted with
00216  *             the same nonce and key.
00217  *
00218  *             There are two common strategies for managing nonces with CTR:
00219  *
00220  *             1. You can handle everything as a single message processed over
00221  *             successive calls to this function. In that case, you want to
00222  *             set \p nonce_counter and \p nc_off to 0 for the first call, and
00223  *             then preserve the values of \p nonce_counter, \p nc_off and \p
00224  *             stream_block across calls to this function as they will be
00225  *             updated by this function.
00226  *
00227  *             With this strategy, you must not encrypt more than 2**64
00228  *             blocks of data with the same key.
00229  *
00230  *             2. You can encrypt separate messages by dividing the \p
00231  *             nonce_counter buffer in two areas: the first one used for a
00232  *             per-message nonce, handled by yourself, and the second one
00233  *             updated by this function internally.
00234  *
00235  *             For example, you might reserve the first 4 bytes for the
00236  *             per-message nonce, and the last 4 bytes for internal use. In that
00237  *             case, before calling this function on a new message you need to
00238  *             set the first 4 bytes of \p nonce_counter to your chosen nonce
00239  *             value, the last 4 to 0, and \p nc_off to 0 (which will cause \p
00240  *             stream_block to be ignored). That way, you can encrypt at most
00241  *             2**32 messages of up to 2**32 blocks each with the same key.
00242  *
00243  *             The per-message nonce (or information sufficient to reconstruct
00244  *             it) needs to be communicated with the ciphertext and must be unique.
00245  *             The recommended way to ensure uniqueness is to use a message
00246  *             counter.
00247  *
00248  *             Note that for both stategies, sizes are measured in blocks and
00249  *             that a Blowfish block is 8 bytes.
00250  *
00251  * \warning    Upon return, \p stream_block contains sensitive data. Its
00252  *             content must not be written to insecure storage and should be
00253  *             securely discarded as soon as it's no longer needed.
00254  *
00255  * \param ctx           The Blowfish context to use. This must be initialized
00256  *                      and bound to a key.
00257  * \param length        The length of the input data in Bytes.
00258  * \param nc_off        The offset in the current stream_block (for resuming
00259  *                      within current cipher stream). The offset pointer
00260  *                      should be \c 0 at the start of a stream and must be
00261  *                      smaller than \c 8. It is updated by this function.
00262  * \param nonce_counter The 64-bit nonce and counter. This must point to a
00263  *                      read/write buffer of length \c 8 Bytes.
00264  * \param stream_block  The saved stream-block for resuming. This must point to
00265  *                      a read/write buffer of length \c 8 Bytes.
00266  * \param input         The input data. This must be a readable buffer of
00267  *                      length \p length Bytes.
00268  * \param output        The output data. This must be a writable buffer of
00269  *                      length \p length Bytes.
00270  *
00271  * \return              \c 0 if successful.
00272  * \return              A negative error code on failure.
00273  */
00274 int mbedtls_blowfish_crypt_ctr( mbedtls_blowfish_context *ctx,
00275                         size_t length,
00276                         size_t *nc_off,
00277                         unsigned char nonce_counter[MBEDTLS_BLOWFISH_BLOCKSIZE],
00278                         unsigned char stream_block[MBEDTLS_BLOWFISH_BLOCKSIZE],
00279                         const unsigned char *input,
00280                         unsigned char *output );
00281 #endif /* MBEDTLS_CIPHER_MODE_CTR */
00282 
00283 #ifdef __cplusplus
00284 }
00285 #endif
00286 
00287 #endif /* blowfish.h */