/*
 * Copyright (C) 2005-2008 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.
 */

/**
 * @defgroup hmac_signer hmac_signer
 * @{ @ingroup hmac_p
 */

#ifndef HMAC_SIGNER_H_
#define HMAC_SIGNER_H_

typedef struct hmac_signer_t hmac_signer_t;

#include <crypto/signers/signer.h>

/**
 * Implementation of signer_t interface using HMAC.
 *
 * HMAC uses a standard hash function implemented in a hasher_t to build a MAC.
 */
struct hmac_signer_t {
	
	/**
	 * generic signer_t interface for this signer
	 */
	signer_t signer_interface;
};

/**
 * Creates a new hmac_signer_t.
 *
 * HMAC signatures are often truncated to shorten them to a more usable, but
 * still secure enough length.
 * Block size must be equal or smaller then the hash algorithms
 * hash.
 *
 * @param algo		algorithm to implement
 * @return			hmac_signer_t, NULL if  not supported
 */
hmac_signer_t *hmac_signer_create(integrity_algorithm_t algo);

#endif /*HMAC_SIGNER_H_ @}*/