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Diffstat (limited to 'src/libstrongswan/crypto/hashers/hasher.h')
| -rw-r--r-- | src/libstrongswan/crypto/hashers/hasher.h | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/src/libstrongswan/crypto/hashers/hasher.h b/src/libstrongswan/crypto/hashers/hasher.h new file mode 100644 index 000000000..6c17f892d --- /dev/null +++ b/src/libstrongswan/crypto/hashers/hasher.h @@ -0,0 +1,159 @@ +/** + * @file hasher.h + * + * @brief Interface hasher_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 HASHER_H_ +#define HASHER_H_ + +typedef enum hash_algorithm_t hash_algorithm_t; +typedef struct hasher_t hasher_t; + +#include <library.h> + +/** + * @brief Algorithms to use for hashing. + * + * Currently only the following algorithms are implemented: + * - HASH_MD5 + * - HASH_SHA1 + * - HASH_SHA256 + * - HASH_SHA384 + * - HASH_SHA512 + * + * @ingroup hashers + */ +enum hash_algorithm_t { + HASH_MD2 = 0, + /** Implemented in class md5_hasher_t */ + HASH_MD5 = 1, + /** Implemented in class sha1_hasher_t */ + HASH_SHA1 = 2, + /** Implemented in class sha2_hasher_t */ + HASH_SHA256 = 3, + /** Implemented in class sha2_hasher_t */ + HASH_SHA384 = 4, + /** Implemented in class sha2_hasher_t */ + HASH_SHA512 = 5, +}; + +#define HASH_SIZE_MD2 16 +#define HASH_SIZE_MD5 16 +#define HASH_SIZE_SHA1 20 +#define HASH_SIZE_SHA256 32 +#define HASH_SIZE_SHA384 48 +#define HASH_SIZE_SHA512 64 +#define HASH_SIZE_MAX 64 + +/** + * enum names for hash_algorithm_t. + */ +extern enum_name_t *hash_algorithm_names; + + +/** + * @brief Generic interface for all hash functions. + * + * @b Constructors: + * - hasher_create() + * + * @ingroup hashers + */ +struct hasher_t { + /** + * @brief Hash data and write it in the buffer. + * + * If the parameter hash is NULL, no result is written back + * an more data can be appended to already hashed data. + * If not, the result is written back and the hasher is reset. + * + * The hash output parameter must hold at least + * hash_t.get_block_size() bytes. + * + * @param this calling object + * @param data data to hash + * @param[out] hash pointer where the hash will be written + */ + void (*get_hash) (hasher_t *this, chunk_t data, u_int8_t *hash); + + /** + * @brief Hash data and allocate space for the hash. + * + * If the parameter hash is NULL, no result is written back + * an more data can be appended to already hashed data. + * If not, the result is written back and the hasher is reset. + * + * @param this calling object + * @param data chunk with data to hash + * @param[out] hash chunk which will hold allocated hash + */ + void (*allocate_hash) (hasher_t *this, chunk_t data, chunk_t *hash); + + /** + * @brief Get the size of the resulting hash. + * + * @param this calling object + * @return hash size in bytes + */ + size_t (*get_hash_size) (hasher_t *this); + + /** + * @brief Resets the hashers state. + * + * @param this calling object + */ + void (*reset) (hasher_t *this); + + /** + * @brief Get the state of the hasher. + * + * A hasher stores internal state information. This state may be + * manipulated to include a "seed" into the hashing operation. It used by + * some exotic protocols (such as AKA). + * The data pointed by chunk may be manipulated, but not replaced nor freed. + * This is more a hack than a feature. The hasher's state may be byte + * order dependant; use with care. + * + * @param this calling object + */ + chunk_t (*get_state) (hasher_t *this); + + /** + * @brief Destroys a hasher object. + * + * @param this calling object + */ + void (*destroy) (hasher_t *this); +}; + +/** + * @brief Generic interface to create a hasher_t. + * + * @param hash_algorithm Algorithm to use for hashing + * @return + * - hasher_t object + * - NULL if algorithm not supported + * + * @ingroup hashers + */ +hasher_t *hasher_create(hash_algorithm_t hash_algorithm); + +#endif /* HASHER_H_ */ |