text: /*	$OpenBSD: des_locl.h,v 1.3 2005/06/13 10:56:44 hshoexer 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/cdefs.h>
  #include <sys/types.h>
  #include <sys/systm.h>
  
  #include "des.h"
  
  /* the following is tweaked from a config script, that is why it is a
   * protected undef/define */
  #ifndef DES_USE_PTR
  #undef DES_USE_PTR
  #endif
  
  #ifndef RAND
  #define RAND
  #endif
  
  #if defined(NOCONST)
  #define const
  #endif
  
  #ifdef __STDC__
  #undef PROTO
  #define PROTO
  #endif
  
  #ifdef RAND
  #define srandom(s) srand(s)
  #define random rand
  #endif
  
  #define ITERATIONS 16
  #define HALF_ITERATIONS 8
  
  /* used in des_read and des_write */
  #define MAXWRITE	(1024*16)
  #define BSIZE		(MAXWRITE+4)
  
  #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)
  
  /* NOTE - c is not incremented as per c2l */
  #define c2ln(c,l1,l2,n)	{ \
  			c+=n; \
  			l1=l2=0; \
  			switch (n) { \
  			case 8: l2 =((u_int32_t)(*(--(c))))<<24L; \
  			case 7: l2|=((u_int32_t)(*(--(c))))<<16L; \
  			case 6: l2|=((u_int32_t)(*(--(c))))<< 8L; \
  			case 5: l2|=((u_int32_t)(*(--(c))));     \
  			case 4: l1 =((u_int32_t)(*(--(c))))<<24L; \
  			case 3: l1|=((u_int32_t)(*(--(c))))<<16L; \
  			case 2: l1|=((u_int32_t)(*(--(c))))<< 8L; \
  			case 1: l1|=((u_int32_t)(*(--(c))));     \
  				} \
  			}
  
  #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))
  
  /* replacements for htonl and ntohl since I have no idea what to do
   * when faced with machines with 8 byte longs. */
  #define HDRSIZE 4
  
  #define n2l(c,l)	(l =((u_int32_t)(*((c)++)))<<24L, \
  			 l|=((u_int32_t)(*((c)++)))<<16L, \
  			 l|=((u_int32_t)(*((c)++)))<< 8L, \
  			 l|=((u_int32_t)(*((c)++))))
  
  #define l2n(l,c)	(*((c)++)=(unsigned char)(((l)>>24L)&0xff), \
  			 *((c)++)=(unsigned char)(((l)>>16L)&0xff), \
  			 *((c)++)=(unsigned char)(((l)>> 8L)&0xff), \
  			 *((c)++)=(unsigned char)(((l)     )&0xff))
  
  /* NOTE - c is not incremented as per l2c */
  #define l2cn(l1,l2,c,n)	{ \
  			c+=n; \
  			switch (n) { \
  			case 8: *(--(c))=(unsigned char)(((l2)>>24L)&0xff); \
  			case 7: *(--(c))=(unsigned char)(((l2)>>16L)&0xff); \
  			case 6: *(--(c))=(unsigned char)(((l2)>> 8L)&0xff); \
  			case 5: *(--(c))=(unsigned char)(((l2)     )&0xff); \
  			case 4: *(--(c))=(unsigned char)(((l1)>>24L)&0xff); \
  			case 3: *(--(c))=(unsigned char)(((l1)>>16L)&0xff); \
  			case 2: *(--(c))=(unsigned char)(((l1)>> 8L)&0xff); \
  			case 1: *(--(c))=(unsigned char)(((l1)     )&0xff); \
  				} \
  			}
  
  /* The changes to this macro may help or hinder, depending on the
   * compiler and the achitecture.  gcc2 always seems to do well :-).
   * Inspired by Dana How <how@isl.stanford.edu>
   * DO NOT use the alternative version on machines with 8 byte longs. */
  #ifdef DES_USR_PTR
  #define D_ENCRYPT(L,R,S) { \
  	u=((R^s[S  ])<<2);	\
  	t= R^s[S+1]; \
  	t=((t>>2)+(t<<30)); \
  	L^= \
  	*(u_int32_t *)(des_SP+0x0100+((t    )&0xfc))+ \
  	*(u_int32_t *)(des_SP+0x0300+((t>> 8)&0xfc))+ \
  	*(u_int32_t *)(des_SP+0x0500+((t>>16)&0xfc))+ \
  	*(u_int32_t *)(des_SP+0x0700+((t>>24)&0xfc))+ \
  	*(u_int32_t *)(des_SP+       ((u    )&0xfc))+ \
  	*(u_int32_t *)(des_SP+0x0200+((u>> 8)&0xfc))+ \
  	*(u_int32_t *)(des_SP+0x0400+((u>>16)&0xfc))+ \
  	*(u_int32_t *)(des_SP+0x0600+((u>>24)&0xfc)); }
  #else /* original version */
  #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]; }
  #endif
  
  	/* 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
  