1 /** 2 * \file blowfish.h 3 * 4 * \brief Blowfish block cipher 5 */ 6 /* 7 * Copyright The Mbed TLS Contributors 8 * SPDX-License-Identifier: Apache-2.0 9 * 10 * Licensed under the Apache License, Version 2.0 (the "License"); you may 11 * not use this file except in compliance with the License. 12 * You may obtain a copy of the License at 13 * 14 * http://www.apache.org/licenses/LICENSE-2.0 15 * 16 * Unless required by applicable law or agreed to in writing, software 17 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 18 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 19 * See the License for the specific language governing permissions and 20 * limitations under the License. 21 */ 22 #ifndef MBEDTLS_BLOWFISH_H 23 #define MBEDTLS_BLOWFISH_H 24 25 #if !defined(MBEDTLS_CONFIG_FILE) 26 #include "mbedtls/config.h" 27 #else 28 #include MBEDTLS_CONFIG_FILE 29 #endif 30 31 #include <stddef.h> 32 #include <stdint.h> 33 34 #include "mbedtls/platform_util.h" 35 36 #define MBEDTLS_BLOWFISH_ENCRYPT 1 37 #define MBEDTLS_BLOWFISH_DECRYPT 0 38 #define MBEDTLS_BLOWFISH_MAX_KEY_BITS 448 39 #define MBEDTLS_BLOWFISH_MIN_KEY_BITS 32 40 #define MBEDTLS_BLOWFISH_ROUNDS 16 /**< Rounds to use. When increasing this value, make sure to extend the initialisation vectors */ 41 #define MBEDTLS_BLOWFISH_BLOCKSIZE 8 /* Blowfish uses 64 bit blocks */ 42 43 #if !defined(MBEDTLS_DEPRECATED_REMOVED) 44 #define MBEDTLS_ERR_BLOWFISH_INVALID_KEY_LENGTH MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( -0x0016 ) 45 #endif /* !MBEDTLS_DEPRECATED_REMOVED */ 46 #define MBEDTLS_ERR_BLOWFISH_BAD_INPUT_DATA -0x0016 /**< Bad input data. */ 47 48 #define MBEDTLS_ERR_BLOWFISH_INVALID_INPUT_LENGTH -0x0018 /**< Invalid data input length. */ 49 50 /* MBEDTLS_ERR_BLOWFISH_HW_ACCEL_FAILED is deprecated and should not be used. 51 */ 52 #define MBEDTLS_ERR_BLOWFISH_HW_ACCEL_FAILED -0x0017 /**< Blowfish hardware accelerator failed. */ 53 54 #ifdef __cplusplus 55 extern "C" { 56 #endif 57 58 #if !defined(MBEDTLS_BLOWFISH_ALT) 59 // Regular implementation 60 // 61 62 /** 63 * \brief Blowfish context structure 64 */ 65 typedef struct mbedtls_blowfish_context 66 { 67 uint32_t P[MBEDTLS_BLOWFISH_ROUNDS + 2]; /*!< Blowfish round keys */ 68 uint32_t S[4][256]; /*!< key dependent S-boxes */ 69 } 70 mbedtls_blowfish_context; 71 72 #else /* MBEDTLS_BLOWFISH_ALT */ 73 #include "blowfish_alt.h" 74 #endif /* MBEDTLS_BLOWFISH_ALT */ 75 76 /** 77 * \brief Initialize a Blowfish context. 78 * 79 * \param ctx The Blowfish context to be initialized. 80 * This must not be \c NULL. 81 */ 82 void mbedtls_blowfish_init( mbedtls_blowfish_context *ctx ); 83 84 /** 85 * \brief Clear a Blowfish context. 86 * 87 * \param ctx The Blowfish context to be cleared. 88 * This may be \c NULL, in which case this function 89 * returns immediately. If it is not \c NULL, it must 90 * point to an initialized Blowfish context. 91 */ 92 void mbedtls_blowfish_free( mbedtls_blowfish_context *ctx ); 93 94 /** 95 * \brief Perform a Blowfish key schedule operation. 96 * 97 * \param ctx The Blowfish context to perform the key schedule on. 98 * \param key The encryption key. This must be a readable buffer of 99 * length \p keybits Bits. 100 * \param keybits The length of \p key in Bits. This must be between 101 * \c 32 and \c 448 and a multiple of \c 8. 102 * 103 * \return \c 0 if successful. 104 * \return A negative error code on failure. 105 */ 106 int mbedtls_blowfish_setkey( mbedtls_blowfish_context *ctx, const unsigned char *key, 107 unsigned int keybits ); 108 109 /** 110 * \brief Perform a Blowfish-ECB block encryption/decryption operation. 111 * 112 * \param ctx The Blowfish context to use. This must be initialized 113 * and bound to a key. 114 * \param mode The mode of operation. Possible values are 115 * #MBEDTLS_BLOWFISH_ENCRYPT for encryption, or 116 * #MBEDTLS_BLOWFISH_DECRYPT for decryption. 117 * \param input The input block. This must be a readable buffer 118 * of size \c 8 Bytes. 119 * \param output The output block. This must be a writable buffer 120 * of size \c 8 Bytes. 121 * 122 * \return \c 0 if successful. 123 * \return A negative error code on failure. 124 */ 125 int mbedtls_blowfish_crypt_ecb( mbedtls_blowfish_context *ctx, 126 int mode, 127 const unsigned char input[MBEDTLS_BLOWFISH_BLOCKSIZE], 128 unsigned char output[MBEDTLS_BLOWFISH_BLOCKSIZE] ); 129 130 #if defined(MBEDTLS_CIPHER_MODE_CBC) 131 /** 132 * \brief Perform a Blowfish-CBC buffer encryption/decryption operation. 133 * 134 * \note Upon exit, the content of the IV is updated so that you can 135 * call the function same function again on the following 136 * block(s) of data and get the same result as if it was 137 * encrypted in one call. This allows a "streaming" usage. 138 * If on the other hand you need to retain the contents of the 139 * IV, you should either save it manually or use the cipher 140 * module instead. 141 * 142 * \param ctx The Blowfish context to use. This must be initialized 143 * and bound to a key. 144 * \param mode The mode of operation. Possible values are 145 * #MBEDTLS_BLOWFISH_ENCRYPT for encryption, or 146 * #MBEDTLS_BLOWFISH_DECRYPT for decryption. 147 * \param length The length of the input data in Bytes. This must be 148 * multiple of \c 8. 149 * \param iv The initialization vector. This must be a read/write buffer 150 * of length \c 8 Bytes. It is updated by this function. 151 * \param input The input data. This must be a readable buffer of length 152 * \p length Bytes. 153 * \param output The output data. This must be a writable buffer of length 154 * \p length Bytes. 155 * 156 * \return \c 0 if successful. 157 * \return A negative error code on failure. 158 */ 159 int mbedtls_blowfish_crypt_cbc( mbedtls_blowfish_context *ctx, 160 int mode, 161 size_t length, 162 unsigned char iv[MBEDTLS_BLOWFISH_BLOCKSIZE], 163 const unsigned char *input, 164 unsigned char *output ); 165 #endif /* MBEDTLS_CIPHER_MODE_CBC */ 166 167 #if defined(MBEDTLS_CIPHER_MODE_CFB) 168 /** 169 * \brief Perform a Blowfish CFB buffer encryption/decryption operation. 170 * 171 * \note Upon exit, the content of the IV is updated so that you can 172 * call the function same function again on the following 173 * block(s) of data and get the same result as if it was 174 * encrypted in one call. This allows a "streaming" usage. 175 * If on the other hand you need to retain the contents of the 176 * IV, you should either save it manually or use the cipher 177 * module instead. 178 * 179 * \param ctx The Blowfish context to use. This must be initialized 180 * and bound to a key. 181 * \param mode The mode of operation. Possible values are 182 * #MBEDTLS_BLOWFISH_ENCRYPT for encryption, or 183 * #MBEDTLS_BLOWFISH_DECRYPT for decryption. 184 * \param length The length of the input data in Bytes. 185 * \param iv_off The offset in the initialiation vector. 186 * The value pointed to must be smaller than \c 8 Bytes. 187 * It is updated by this function to support the aforementioned 188 * streaming usage. 189 * \param iv The initialization vector. This must be a read/write buffer 190 * of size \c 8 Bytes. It is updated after use. 191 * \param input The input data. This must be a readable buffer of length 192 * \p length Bytes. 193 * \param output The output data. This must be a writable buffer of length 194 * \p length Bytes. 195 * 196 * \return \c 0 if successful. 197 * \return A negative error code on failure. 198 */ 199 int mbedtls_blowfish_crypt_cfb64( mbedtls_blowfish_context *ctx, 200 int mode, 201 size_t length, 202 size_t *iv_off, 203 unsigned char iv[MBEDTLS_BLOWFISH_BLOCKSIZE], 204 const unsigned char *input, 205 unsigned char *output ); 206 #endif /*MBEDTLS_CIPHER_MODE_CFB */ 207 208 #if defined(MBEDTLS_CIPHER_MODE_CTR) 209 /** 210 * \brief Perform a Blowfish-CTR buffer encryption/decryption operation. 211 * 212 * \warning You must never reuse a nonce value with the same key. Doing so 213 * would void the encryption for the two messages encrypted with 214 * the same nonce and key. 215 * 216 * There are two common strategies for managing nonces with CTR: 217 * 218 * 1. You can handle everything as a single message processed over 219 * successive calls to this function. In that case, you want to 220 * set \p nonce_counter and \p nc_off to 0 for the first call, and 221 * then preserve the values of \p nonce_counter, \p nc_off and \p 222 * stream_block across calls to this function as they will be 223 * updated by this function. 224 * 225 * With this strategy, you must not encrypt more than 2**64 226 * blocks of data with the same key. 227 * 228 * 2. You can encrypt separate messages by dividing the \p 229 * nonce_counter buffer in two areas: the first one used for a 230 * per-message nonce, handled by yourself, and the second one 231 * updated by this function internally. 232 * 233 * For example, you might reserve the first 4 bytes for the 234 * per-message nonce, and the last 4 bytes for internal use. In that 235 * case, before calling this function on a new message you need to 236 * set the first 4 bytes of \p nonce_counter to your chosen nonce 237 * value, the last 4 to 0, and \p nc_off to 0 (which will cause \p 238 * stream_block to be ignored). That way, you can encrypt at most 239 * 2**32 messages of up to 2**32 blocks each with the same key. 240 * 241 * The per-message nonce (or information sufficient to reconstruct 242 * it) needs to be communicated with the ciphertext and must be unique. 243 * The recommended way to ensure uniqueness is to use a message 244 * counter. 245 * 246 * Note that for both stategies, sizes are measured in blocks and 247 * that a Blowfish block is 8 bytes. 248 * 249 * \warning Upon return, \p stream_block contains sensitive data. Its 250 * content must not be written to insecure storage and should be 251 * securely discarded as soon as it's no longer needed. 252 * 253 * \param ctx The Blowfish context to use. This must be initialized 254 * and bound to a key. 255 * \param length The length of the input data in Bytes. 256 * \param nc_off The offset in the current stream_block (for resuming 257 * within current cipher stream). The offset pointer 258 * should be \c 0 at the start of a stream and must be 259 * smaller than \c 8. It is updated by this function. 260 * \param nonce_counter The 64-bit nonce and counter. This must point to a 261 * read/write buffer of length \c 8 Bytes. 262 * \param stream_block The saved stream-block for resuming. This must point to 263 * a read/write buffer of length \c 8 Bytes. 264 * \param input The input data. This must be a readable buffer of 265 * length \p length Bytes. 266 * \param output The output data. This must be a writable buffer of 267 * length \p length Bytes. 268 * 269 * \return \c 0 if successful. 270 * \return A negative error code on failure. 271 */ 272 int mbedtls_blowfish_crypt_ctr( mbedtls_blowfish_context *ctx, 273 size_t length, 274 size_t *nc_off, 275 unsigned char nonce_counter[MBEDTLS_BLOWFISH_BLOCKSIZE], 276 unsigned char stream_block[MBEDTLS_BLOWFISH_BLOCKSIZE], 277 const unsigned char *input, 278 unsigned char *output ); 279 #endif /* MBEDTLS_CIPHER_MODE_CTR */ 280 281 #ifdef __cplusplus 282 } 283 #endif 284 285 #endif /* blowfish.h */ 286