strongswan/Source/charon/utils/randomizer.h

123 lines
3.4 KiB
C

/**
* @file randomizer.h
*
* @brief Interface of randomizer_t.
*
*/
/*
* Copyright (C) 2005 Jan Hutter, Martin Willi
* 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 RANDOMIZER_H_
#define RANDOMIZER_H_
#include <types.h>
/**
* Default random device used when no device is given.
*/
#define DEFAULT_RANDOM_DEVICE "/dev/random"
/**
* Pseudo random device used when no device is given.
*/
#define DEFAULT_PSEUDO_RANDOM_DEVICE "/dev/urandom"
typedef struct randomizer_t randomizer_t;
/**
* @brief Class used to get random and pseudo random values.
*
* This class is thread save as file system read calls are thread save.
*
* @b Constructors:
* - randomizer_create()
* - randomizer_create_on_devices()
*
* @ingroup utils
*/
struct randomizer_t {
/**
* @brief Reads a specific number of bytes from random device.
*
* @param this calling randomizer_t object
* @param bytes number of bytes to read
* @param[out] buffer pointer to buffer where to write the data in.
* Size of buffer has to be at least bytes.
*/
void (*get_random_bytes) (randomizer_t *this,size_t bytes, u_int8_t *buffer);
/**
* @brief Allocates space and writes in random bytes.
*
* @param this calling randomizer_t object
* @param bytes number of bytes to allocate
* @param[out] chunk chunk which will hold the allocated random bytes
*/
void (*allocate_random_bytes) (randomizer_t *this, size_t bytes, chunk_t *chunk);
/**
* @brief Reads a specific number of bytes from pseudo random device.
*
* @param this calling randomizer_t object
* @param bytes number of bytes to read
* @param[out] buffer pointer to buffer where to write the data in.
* size of buffer has to be at least bytes.
*/
void (*get_pseudo_random_bytes) (randomizer_t *this,size_t bytes, u_int8_t *buffer);
/**
* @brief Allocates space and writes in pseudo random bytes.
*
* @param this calling randomizer_t object
* @param bytes number of bytes to allocate
* @param[out] chunk chunk which will hold the allocated random bytes
*/
void (*allocate_pseudo_random_bytes) (randomizer_t *this, size_t bytes, chunk_t *chunk);
/**
* @brief Destroys a randomizer_t object.
*
* @param this randomizer_t object to destroy
*/
void (*destroy) (randomizer_t *this);
};
/**
* @brief Creates a randomizer_t object
*
* @return
* - created randomizer_t, or
* - NULL if failed
*
* @ingroup utils
*/
randomizer_t *randomizer_create();
/**
* @brief Creates an randomizer_t object with specific random device names.
*
* @param random_dev_name device name for random values, etc /dev/random
* @param prandom_dev_name device name for pseudo random values, etc /dev/urandom
* @return randomizer_t object
*
* @ingroup utils
*/
randomizer_t *randomizer_create_on_devices(char * random_dev_name,char * prandom_dev_name);
#endif /*RANDOMIZER_H_*/