/*	$OpenBSD: des_locl.h,v 1.6 2015/01/16 15:29:45 tedu Exp $	*/

/* lib/des/des_locl.h */
/* Copyright (C) 1995 Eric Young (eay@mincom.oz.au)
 * All rights reserved.
 * 
 * This file is part of an SSL implementation written
 * by Eric Young (eay@mincom.oz.au).
 * The implementation was written so as to conform with Netscapes SSL
 * specification.  This library and applications are
 * FREE FOR COMMERCIAL AND NON-COMMERCIAL USE
 * as long as the following conditions are aheared to.
 * 
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.  If this code is used in a product,
 * Eric Young should be given attribution as the author of the parts used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 * 
 * 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 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    This product includes software developed by Eric Young (eay@mincom.oz.au)
 * 
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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 OR CONTRIBUTORS 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.
 * 
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#ifndef HEADER_DES_LOCL_H
#define HEADER_DES_LOCL_H

#include <sys/types.h>
#include <sys/systm.h>

typedef unsigned char des_cblock[8];
typedef struct des_ks_struct
	{
	union	{
		des_cblock cblock;
		/* make sure things are correct size on machines with
		 * 8 byte longs */
		int32_t pad[2];
		} ks;
	} des_key_schedule[16];

#define DES_KEY_SZ 	(sizeof(des_cblock))
#define DES_SCHEDULE_SZ (sizeof(des_key_schedule))


void des_encrypt(u_int32_t *data,des_key_schedule ks, int enc);
void des_encrypt2(u_int32_t *data,des_key_schedule ks, int enc);


#define ITERATIONS 16
#define HALF_ITERATIONS 8


#define c2l(c,l)	(l =((u_int32_t)(*((c)++)))    , \
			 l|=((u_int32_t)(*((c)++)))<< 8L, \
			 l|=((u_int32_t)(*((c)++)))<<16L, \
			 l|=((u_int32_t)(*((c)++)))<<24L)

#define l2c(l,c)	(*((c)++)=(unsigned char)(((l)     )&0xff), \
			 *((c)++)=(unsigned char)(((l)>> 8L)&0xff), \
			 *((c)++)=(unsigned char)(((l)>>16L)&0xff), \
			 *((c)++)=(unsigned char)(((l)>>24L)&0xff))

#define D_ENCRYPT(Q,R,S) {\
	u=(R^s[S  ]); \
	t=R^s[S+1]; \
	t=((t>>4L)+(t<<28L)); \
	Q^=	des_SPtrans[1][(t     )&0x3f]| \
		des_SPtrans[3][(t>> 8L)&0x3f]| \
		des_SPtrans[5][(t>>16L)&0x3f]| \
		des_SPtrans[7][(t>>24L)&0x3f]| \
		des_SPtrans[0][(u     )&0x3f]| \
		des_SPtrans[2][(u>> 8L)&0x3f]| \
		des_SPtrans[4][(u>>16L)&0x3f]| \
		des_SPtrans[6][(u>>24L)&0x3f]; }

	/* IP and FP
	 * The problem is more of a geometric problem that random bit fiddling.
	 0  1  2  3  4  5  6  7      62 54 46 38 30 22 14  6
	 8  9 10 11 12 13 14 15      60 52 44 36 28 20 12  4
	16 17 18 19 20 21 22 23      58 50 42 34 26 18 10  2
	24 25 26 27 28 29 30 31  to  56 48 40 32 24 16  8  0

	32 33 34 35 36 37 38 39      63 55 47 39 31 23 15  7
	40 41 42 43 44 45 46 47      61 53 45 37 29 21 13  5
	48 49 50 51 52 53 54 55      59 51 43 35 27 19 11  3
	56 57 58 59 60 61 62 63      57 49 41 33 25 17  9  1

	The output has been subject to swaps of the form
	0 1 -> 3 1 but the odd and even bits have been put into
	2 3    2 0
	different words.  The main trick is to remember that
	t=((l>>size)^r)&(mask);
	r^=t;
	l^=(t<<size);
	can be used to swap and move bits between words.

	So l =  0  1  2  3  r = 16 17 18 19
	        4  5  6  7      20 21 22 23
	        8  9 10 11      24 25 26 27
	       12 13 14 15      28 29 30 31
	becomes (for size == 2 and mask == 0x3333)
	   t =   2^16  3^17 -- --   l =  0  1 16 17  r =  2  3 18 19
		 6^20  7^21 -- --        4  5 20 21       6  7 22 23
		10^24 11^25 -- --        8  9 24 25      10 11 24 25
		14^28 15^29 -- --       12 13 28 29      14 15 28 29

	Thanks for hints from Richard Outerbridge - he told me IP&FP
	could be done in 15 xor, 10 shifts and 5 ands.
	When I finally started to think of the problem in 2D
	I first got ~42 operations without xors.  When I remembered
	how to use xors :-) I got it to its final state.
	*/
#define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\
	(b)^=(t),\
	(a)^=((t)<<(n)))

#define IP(l,r) \
	{ \
	register u_int32_t tt; \
	PERM_OP(r,l,tt, 4,0x0f0f0f0fL); \
	PERM_OP(l,r,tt,16,0x0000ffffL); \
	PERM_OP(r,l,tt, 2,0x33333333L); \
	PERM_OP(l,r,tt, 8,0x00ff00ffL); \
	PERM_OP(r,l,tt, 1,0x55555555L); \
	}

#define FP(l,r) \
	{ \
	register u_int32_t tt; \
	PERM_OP(l,r,tt, 1,0x55555555L); \
	PERM_OP(r,l,tt, 8,0x00ff00ffL); \
	PERM_OP(l,r,tt, 2,0x33333333L); \
	PERM_OP(r,l,tt,16,0x0000ffffL); \
	PERM_OP(l,r,tt, 4,0x0f0f0f0fL); \
	}
#endif