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Diffstat (limited to 'src/libstrongswan/crypto/hmac.h')
-rw-r--r-- | src/libstrongswan/crypto/hmac.h | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/src/libstrongswan/crypto/hmac.h b/src/libstrongswan/crypto/hmac.h new file mode 100644 index 000000000..d320bc5aa --- /dev/null +++ b/src/libstrongswan/crypto/hmac.h @@ -0,0 +1,117 @@ +/** + * @file hmac.h + * + * @brief Interface of hmac_t. + */ + +/* + * Copyright (C) 2005-2006 Martin Willi + * Copyright (C) 2005 Jan Hutter + * Hochschule fuer Technik Rapperswil + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + */ + +#ifndef HMAC_H_ +#define HMAC_H_ + +typedef struct hmac_t hmac_t; + +#include <crypto/hashers/hasher.h> + +/** + * @brief Message authentication using hash functions. + * + * This class implements the message authenticaion algorithm + * described in RFC2104. It uses a hash function, wich must + * be implemented as a hasher_t class. + * + * See http://www.faqs.org/rfcs/rfc2104.html for RFC. + * @see + * - hasher_t + * - prf_hmac_t + * + * @b Constructors: + * - hmac_create() + * + * @ingroup transforms + */ +struct hmac_t { + /** + * @brief Generate message authentication code. + * + * If buffer is NULL, no result is given back. A next call will + * append the data to already supplied data. If buffer is not NULL, + * the mac of all apended data is calculated, returned and the + * state of the hmac_t is reseted. + * + * @param this calling object + * @param data chunk of data to authenticate + * @param[out] buffer pointer where the generated bytes will be written + */ + void (*get_mac) (hmac_t *this, chunk_t data, u_int8_t *buffer); + + /** + * @brief Generates message authentication code and + * allocate space for them. + * + * If chunk is NULL, no result is given back. A next call will + * append the data to already supplied. If chunk is not NULL, + * the mac of all apended data is calculated, returned and the + * state of the hmac_t reset; + * + * @param this calling object + * @param data chunk of data to authenticate + * @param[out] chunk chunk which will hold generated bytes + */ + void (*allocate_mac) (hmac_t *this, chunk_t data, chunk_t *chunk); + + /** + * @brief Get the block size of this hmac_t object. + * + * @param this calling object + * @return block size in bytes + */ + size_t (*get_block_size) (hmac_t *this); + + /** + * @brief Set the key for this hmac_t object. + * + * Any key length is accepted. + * + * @param this calling object + * @param key key to set + */ + void (*set_key) (hmac_t *this, chunk_t key); + + /** + * @brief Destroys a hmac_t object. + * + * @param this calling object + */ + void (*destroy) (hmac_t *this); +}; + +/** + * @brief Creates a new hmac_t object. + * + * Creates a hasher_t object internally. + * + * @param hash_algorithm hash algorithm to use + * @return + * - hmac_t object + * - NULL if hash algorithm is not supported + * + * @ingroup transforms + */ +hmac_t *hmac_create(hash_algorithm_t hash_algorithm); + +#endif /*HMAC_H_*/ |