/** * \file blowfish.h * * \brief Blowfish block cipher */ /* * Copyright The Mbed TLS Contributors * SPDX-License-Identifier: Apache-2.0 * * Licensed under the Apache License, Version 2.0 (the "License"); you may * not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef MBEDTLS_BLOWFISH_H #define MBEDTLS_BLOWFISH_H #if !defined(MBEDTLS_CONFIG_FILE) #include "mbedtls/config.h" #else #include MBEDTLS_CONFIG_FILE #endif #include #include #include "mbedtls/platform_util.h" #define MBEDTLS_BLOWFISH_ENCRYPT 1 #define MBEDTLS_BLOWFISH_DECRYPT 0 #define MBEDTLS_BLOWFISH_MAX_KEY_BITS 448 #define MBEDTLS_BLOWFISH_MIN_KEY_BITS 32 #define MBEDTLS_BLOWFISH_ROUNDS 16 /**< Rounds to use. When increasing this value, make sure to extend the initialisation vectors */ #define MBEDTLS_BLOWFISH_BLOCKSIZE 8 /* Blowfish uses 64 bit blocks */ #if !defined(MBEDTLS_DEPRECATED_REMOVED) #define MBEDTLS_ERR_BLOWFISH_INVALID_KEY_LENGTH MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( -0x0016 ) #endif /* !MBEDTLS_DEPRECATED_REMOVED */ #define MBEDTLS_ERR_BLOWFISH_BAD_INPUT_DATA -0x0016 /**< Bad input data. */ #define MBEDTLS_ERR_BLOWFISH_INVALID_INPUT_LENGTH -0x0018 /**< Invalid data input length. */ /* MBEDTLS_ERR_BLOWFISH_HW_ACCEL_FAILED is deprecated and should not be used. */ #define MBEDTLS_ERR_BLOWFISH_HW_ACCEL_FAILED -0x0017 /**< Blowfish hardware accelerator failed. */ #ifdef __cplusplus extern "C" { #endif #if !defined(MBEDTLS_BLOWFISH_ALT) // Regular implementation // /** * \brief Blowfish context structure */ typedef struct mbedtls_blowfish_context { uint32_t P[MBEDTLS_BLOWFISH_ROUNDS + 2]; /*!< Blowfish round keys */ uint32_t S[4][256]; /*!< key dependent S-boxes */ } mbedtls_blowfish_context; #else /* MBEDTLS_BLOWFISH_ALT */ #include "blowfish_alt.h" #endif /* MBEDTLS_BLOWFISH_ALT */ /** * \brief Initialize a Blowfish context. * * \param ctx The Blowfish context to be initialized. * This must not be \c NULL. */ void mbedtls_blowfish_init( mbedtls_blowfish_context *ctx ); /** * \brief Clear a Blowfish context. * * \param ctx The Blowfish context to be cleared. * This may be \c NULL, in which case this function * returns immediately. If it is not \c NULL, it must * point to an initialized Blowfish context. */ void mbedtls_blowfish_free( mbedtls_blowfish_context *ctx ); /** * \brief Perform a Blowfish key schedule operation. * * \param ctx The Blowfish context to perform the key schedule on. * \param key The encryption key. This must be a readable buffer of * length \p keybits Bits. * \param keybits The length of \p key in Bits. This must be between * \c 32 and \c 448 and a multiple of \c 8. * * \return \c 0 if successful. * \return A negative error code on failure. */ int mbedtls_blowfish_setkey( mbedtls_blowfish_context *ctx, const unsigned char *key, unsigned int keybits ); /** * \brief Perform a Blowfish-ECB block encryption/decryption operation. * * \param ctx The Blowfish context to use. This must be initialized * and bound to a key. * \param mode The mode of operation. Possible values are * #MBEDTLS_BLOWFISH_ENCRYPT for encryption, or * #MBEDTLS_BLOWFISH_DECRYPT for decryption. * \param input The input block. This must be a readable buffer * of size \c 8 Bytes. * \param output The output block. This must be a writable buffer * of size \c 8 Bytes. * * \return \c 0 if successful. * \return A negative error code on failure. */ int mbedtls_blowfish_crypt_ecb( mbedtls_blowfish_context *ctx, int mode, const unsigned char input[MBEDTLS_BLOWFISH_BLOCKSIZE], unsigned char output[MBEDTLS_BLOWFISH_BLOCKSIZE] ); #if defined(MBEDTLS_CIPHER_MODE_CBC) /** * \brief Perform a Blowfish-CBC buffer encryption/decryption operation. * * \note Upon exit, the content of the IV is updated so that you can * call the function same function again on the following * block(s) of data and get the same result as if it was * encrypted in one call. This allows a "streaming" usage. * If on the other hand you need to retain the contents of the * IV, you should either save it manually or use the cipher * module instead. * * \param ctx The Blowfish context to use. This must be initialized * and bound to a key. * \param mode The mode of operation. Possible values are * #MBEDTLS_BLOWFISH_ENCRYPT for encryption, or * #MBEDTLS_BLOWFISH_DECRYPT for decryption. * \param length The length of the input data in Bytes. This must be * multiple of \c 8. * \param iv The initialization vector. This must be a read/write buffer * of length \c 8 Bytes. It is updated by this function. * \param input The input data. This must be a readable buffer of length * \p length Bytes. * \param output The output data. This must be a writable buffer of length * \p length Bytes. * * \return \c 0 if successful. * \return A negative error code on failure. */ int mbedtls_blowfish_crypt_cbc( mbedtls_blowfish_context *ctx, int mode, size_t length, unsigned char iv[MBEDTLS_BLOWFISH_BLOCKSIZE], const unsigned char *input, unsigned char *output ); #endif /* MBEDTLS_CIPHER_MODE_CBC */ #if defined(MBEDTLS_CIPHER_MODE_CFB) /** * \brief Perform a Blowfish CFB buffer encryption/decryption operation. * * \note Upon exit, the content of the IV is updated so that you can * call the function same function again on the following * block(s) of data and get the same result as if it was * encrypted in one call. This allows a "streaming" usage. * If on the other hand you need to retain the contents of the * IV, you should either save it manually or use the cipher * module instead. * * \param ctx The Blowfish context to use. This must be initialized * and bound to a key. * \param mode The mode of operation. Possible values are * #MBEDTLS_BLOWFISH_ENCRYPT for encryption, or * #MBEDTLS_BLOWFISH_DECRYPT for decryption. * \param length The length of the input data in Bytes. * \param iv_off The offset in the initialiation vector. * The value pointed to must be smaller than \c 8 Bytes. * It is updated by this function to support the aforementioned * streaming usage. * \param iv The initialization vector. This must be a read/write buffer * of size \c 8 Bytes. It is updated after use. * \param input The input data. This must be a readable buffer of length * \p length Bytes. * \param output The output data. This must be a writable buffer of length * \p length Bytes. * * \return \c 0 if successful. * \return A negative error code on failure. */ int mbedtls_blowfish_crypt_cfb64( mbedtls_blowfish_context *ctx, int mode, size_t length, size_t *iv_off, unsigned char iv[MBEDTLS_BLOWFISH_BLOCKSIZE], const unsigned char *input, unsigned char *output ); #endif /*MBEDTLS_CIPHER_MODE_CFB */ #if defined(MBEDTLS_CIPHER_MODE_CTR) /** * \brief Perform a Blowfish-CTR buffer encryption/decryption operation. * * \warning You must never reuse a nonce value with the same key. Doing so * would void the encryption for the two messages encrypted with * the same nonce and key. * * There are two common strategies for managing nonces with CTR: * * 1. You can handle everything as a single message processed over * successive calls to this function. In that case, you want to * set \p nonce_counter and \p nc_off to 0 for the first call, and * then preserve the values of \p nonce_counter, \p nc_off and \p * stream_block across calls to this function as they will be * updated by this function. * * With this strategy, you must not encrypt more than 2**64 * blocks of data with the same key. * * 2. You can encrypt separate messages by dividing the \p * nonce_counter buffer in two areas: the first one used for a * per-message nonce, handled by yourself, and the second one * updated by this function internally. * * For example, you might reserve the first 4 bytes for the * per-message nonce, and the last 4 bytes for internal use. In that * case, before calling this function on a new message you need to * set the first 4 bytes of \p nonce_counter to your chosen nonce * value, the last 4 to 0, and \p nc_off to 0 (which will cause \p * stream_block to be ignored). That way, you can encrypt at most * 2**32 messages of up to 2**32 blocks each with the same key. * * The per-message nonce (or information sufficient to reconstruct * it) needs to be communicated with the ciphertext and must be unique. * The recommended way to ensure uniqueness is to use a message * counter. * * Note that for both stategies, sizes are measured in blocks and * that a Blowfish block is 8 bytes. * * \warning Upon return, \p stream_block contains sensitive data. Its * content must not be written to insecure storage and should be * securely discarded as soon as it's no longer needed. * * \param ctx The Blowfish context to use. This must be initialized * and bound to a key. * \param length The length of the input data in Bytes. * \param nc_off The offset in the current stream_block (for resuming * within current cipher stream). The offset pointer * should be \c 0 at the start of a stream and must be * smaller than \c 8. It is updated by this function. * \param nonce_counter The 64-bit nonce and counter. This must point to a * read/write buffer of length \c 8 Bytes. * \param stream_block The saved stream-block for resuming. This must point to * a read/write buffer of length \c 8 Bytes. * \param input The input data. This must be a readable buffer of * length \p length Bytes. * \param output The output data. This must be a writable buffer of * length \p length Bytes. * * \return \c 0 if successful. * \return A negative error code on failure. */ int mbedtls_blowfish_crypt_ctr( mbedtls_blowfish_context *ctx, size_t length, size_t *nc_off, unsigned char nonce_counter[MBEDTLS_BLOWFISH_BLOCKSIZE], unsigned char stream_block[MBEDTLS_BLOWFISH_BLOCKSIZE], const unsigned char *input, unsigned char *output ); #endif /* MBEDTLS_CIPHER_MODE_CTR */ #ifdef __cplusplus } #endif #endif /* blowfish.h */