root/sys/crypto/des_locl.h
/*      $OpenBSD: des_locl.h,v 1.7 2015/12/10 21:00:51 naddy 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_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