/*
************************************************************************
**
**	Copyright (c) 2011 by
**		Core|Vision B.V.
**		Cereslaan 10b
**		5384 VT  Heesch
**		The Netherlands
**
**	All Rights Reserved
**
************************************************************************
*/
/*
************************************************************************
**
**	Project name:   Dual Inventive: Utility Library
**	Filename:       cp3000-encrypt.h
**	Author:			Jack Weeland
**	Date:			December 1, 2011
**	File version:	$Revision: 1.4 $
**					$Date: 2013/04/15 15:37:42 $
**
************************************************************************
*/
/*
************************************************************************
**
**	CP3000 block cypher encryption
**
************************************************************************
*/

#ifndef	__CP3000_ENCRYPT_H
#define	__CP3000_ENCRYPT_H

#include <di-util/cp3000.h>

/*
**	Exported functions
*/
// Initialize and destroy encryption state
cp3000_key_t cp3000_init_encrypt_state();
void cp3000_deinit_encrypt_state(cp3000_key_t);

// Set encryption and decryptions keys and initialize state vector;
//	the key _must_ be set, but the vectors will be zero-initialized
// The key size _must_ be 128, 192 or 256 bits (16, 24 or 32 bytes)
int cp3000_encrypt_set_key(cp3000_key_t, const void *key, int key_sz);
int cp3000_encrypt_set_state(cp3000_key_t, const void *vector, int vector_sz);
int cp3000_decrypt_set_state(cp3000_key_t, const void *vector, int vector_sz);

// Encrypt data buffer
// Parameters:
//	- encryption state
//	- input and output data buffer and size
// Note:
//	The input buffer is padded with random data bytes for better
//	security. For that reason, the output buffer should be larger
//	than the input buffer.
int cp3000_encrypt(
	cp3000_key_t,
	const void *in, int in_sz,
	void* out,      int out_sz
);

// Decrypt data buffer
// Parameters:
//	- encryption state
//	- input and output data buffer and size
// Note:
//	The input and output buffers should be the same size; if the
//	sizes are diffent, then the minimum value will be used. Surplus
//	bytes are simply ignored.
int cp3000_decrypt(
	cp3000_key_t,
	const void *in, int in_sz,
	void* out,      int out_sz
);

// Fill a buffer with random data
// Returns:
//	< 0 on error
//	0 when the data is _not_ unpredictable
//	1 when the dats is unpredictable and thus cryptographically okay
int cp3000_random_bytes(void *buffer, int buffer_sz);

#endif	/* __CP3000_ENCRYPT_H */