/* $OpenBSD: math_2n.h,v 1.7 2004/04/15 18:39:26 deraadt Exp $	 */
/* $EOM: math_2n.h,v 1.9 1999/04/17 23:20:32 niklas Exp $	 */

/*
 * Copyright (c) 1998 Niels Provos.  All rights reserved.
 * Copyright (c) 1999 Niklas Hallqvist.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * This code was written under funding by Ericsson Radio Systems.
 */

#ifndef _MATH_2N_H
#define _MATH_2N_H_

/*
 * The chunk size we use is variable, this allows speed ups
 * for processors like the Alpha with 64bit words.
 * XXX - b2n_mask is only up to 32 bit at the moment.
 */

#define USE_32BIT		/* XXX - This obviously needs fixing */

#ifdef USE_32BIT
#define CHUNK_TYPE	u_int32_t
#define CHUNK_BITS	32
#define CHUNK_SHIFTS	5
#define CHUNK_BMASK	0xffffffff
#define CHUNK_MASK	(CHUNK_BITS - 1)
#define CHUNK_BYTES	(CHUNK_BITS >> 3)
#define CHUNK_NIBBLES	(CHUNK_BITS >> 2)
#else
#define CHUNK_TYPE	u_int8_t
#define CHUNK_BITS	8
#define CHUNK_SHIFTS	3
#define CHUNK_BMASK	0xff
#define CHUNK_MASK	(CHUNK_BITS - 1)
#define CHUNK_BYTES	(CHUNK_BITS >> 3)
#define CHUNK_NIBBLES	(CHUNK_BITS >> 2)
#endif

extern CHUNK_TYPE b2n_mask[CHUNK_BITS];

/* An element of GF(2**n), n = bits */

typedef struct {
	u_int16_t       chunks;
	u_int16_t       bits;
	u_int8_t        dirty;	/* Sig bits are dirty */
	CHUNK_TYPE     *limp;
}               _b2n;

typedef _b2n   *b2n_ptr;
typedef _b2n    b2n_t[1];

#define B2N_SET(x,y) do \
  { \
    (x)->chunks = (y)->chunks; \
    (x)->bits = (y)->bits; \
    (x)->limp = (y)->limp; \
    (x)->dirty = (y)->dirty; \
  } \
while (0)

#define B2N_SWAP(x,y) do \
  { \
    b2n_t _t_; \
\
    B2N_SET (_t_, (x)); \
    B2N_SET ((x), (y)); \
    B2N_SET ((y), _t_); \
  } \
while (0)

#define B2N_MIN(x,y) ((x)->chunks > (y)->chunks ? (y) : (x))
#define B2N_MAX(x,y) ((x)->chunks > (y)->chunks ? (x) : (y))

int             b2n_3mul(b2n_ptr, b2n_ptr);
int             b2n_add(b2n_ptr, b2n_ptr, b2n_ptr);
int             b2n_cmp(b2n_ptr, b2n_ptr);
int             b2n_cmp_null(b2n_ptr);
int             b2n_div(b2n_ptr, b2n_ptr, b2n_ptr, b2n_ptr);
int             b2n_div_mod(b2n_ptr, b2n_ptr, b2n_ptr, b2n_ptr);
int             b2n_div_q(b2n_ptr, b2n_ptr, b2n_ptr);
int             b2n_div_r(b2n_ptr, b2n_ptr, b2n_ptr);
int             b2n_exp_mod(b2n_ptr, b2n_ptr, u_int32_t, b2n_ptr);
void            b2n_init(b2n_ptr);
void            b2n_clear(b2n_ptr);
int             b2n_gcd(b2n_ptr, b2n_ptr, b2n_ptr);
int             b2n_halftrace(b2n_ptr, b2n_ptr, b2n_ptr);
int             b2n_lshift(b2n_ptr, b2n_ptr, unsigned int);
int             b2n_mod(b2n_ptr, b2n_ptr, b2n_ptr);
int             b2n_mul(b2n_ptr, b2n_ptr, b2n_ptr);
int             b2n_mul_inv(b2n_ptr, b2n_ptr, b2n_ptr);
int             b2n_nadd(b2n_ptr, b2n_ptr, b2n_ptr);
int             b2n_nsub(b2n_ptr, b2n_ptr, b2n_ptr);
void            b2n_print(b2n_ptr);
int             b2n_random(b2n_ptr, u_int32_t);
int             b2n_resize(b2n_ptr, unsigned int);
int             b2n_rshift(b2n_ptr, b2n_ptr, unsigned int);
int             b2n_set(b2n_ptr, b2n_ptr);
int             b2n_set_null(b2n_ptr);
int             b2n_set_str(b2n_ptr, char *);
int             b2n_set_ui(b2n_ptr, unsigned int);
u_int32_t       b2n_sigbit(b2n_ptr);
int             b2n_snprint(char *, size_t, b2n_ptr);
int             b2n_sqrt(b2n_ptr, b2n_ptr, b2n_ptr);
int             b2n_square(b2n_ptr, b2n_ptr);
#define b2n_sub b2n_add
int             b2n_trace(b2n_ptr, b2n_ptr, b2n_ptr);

#endif				/* _MATH_2N_H_ */