// license:BSD-3
// copyright-holders:Andreas Naive
#ifndef _NS10CRYPT_H_
#define _NS10CRYPT_H_
class gf2_reducer // helper class
{
public:
gf2_reducer();
int gf2_reduce(UINT64 num)const;
private:
int _gf2Reduction[0x10000];
};
class ns10_decrypter_device : public device_t
{
public:
// this encodes the decryption logic, which varies per game
// and is probably hard-coded into the CPLD
struct ns10_crypto_logic
{
UINT64 eMask[16];
UINT64 dMask[16];
UINT16 xMask;
UINT16(*nonlinear_calculation)(UINT64, UINT64, const gf2_reducer&); // preliminary encoding; need research
};
void activate(int iv);
void deactivate();
bool is_active()const;
UINT16 decrypt(UINT16 cipherword);
protected:
ns10_decrypter_device(
device_type type, const ns10_decrypter_device::ns10_crypto_logic &logic,
const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
private:
UINT16 _mask;
UINT64 _previous_cipherwords;
UINT64 _previous_plainwords;
bool _active;
const ns10_crypto_logic& _logic;
static const int initSbox[16];
const gf2_reducer *_reducer;
void device_start();
void init(int iv);
};
// game-specific devices
class chocovdr_decrypter_device : public ns10_decrypter_device
{
public:
chocovdr_decrypter_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
};
class gamshara_decrypter_device : public ns10_decrypter_device
{
public:
gamshara_decrypter_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
};
class gjspace_decrypter_device : public ns10_decrypter_device
{
public:
gjspace_decrypter_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
};
class knpuzzle_decrypter_device : public ns10_decrypter_device
{
public:
knpuzzle_decrypter_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
};
class konotako_decrypter_device : public ns10_decrypter_device
{
public:
konotako_decrypter_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
};
class nflclsfb_decrypter_device : public ns10_decrypter_device
{
public:
nflclsfb_decrypter_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
};
class startrgn_decrypter_device : public ns10_decrypter_device
{
public:
startrgn_decrypter_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
};
extern const device_type CHOCOVDR_DECRYPTER;
extern const device_type GAMSHARA_DECRYPTER;
extern const device_type GJSPACE_DECRYPTER;
extern const device_type KNPUZZLE_DECRYPTER;
extern const device_type KONOTAKO_DECRYPTER;
extern const device_type NFLCLSFB_DECRYPTER;
extern const device_type STARTRGN_DECRYPTER;
#endif