/*      $FreeBSD: src/sys/crypto/des/des_setkey.c,v 1.1.2.4 2002/03/26 10:12:25 ume Exp $       */
/*      $KAME: des_setkey.c,v 1.7 2001/09/10 04:03:58 itojun Exp $      */

/* crypto/des/set_key.c */
/* Copyright (C) 1995-1996 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.]
 */

/* set_key.c v 1.4 eay 24/9/91
 * 1.4 Speed up by 400% :-)
 * 1.3 added register declarations.
 * 1.2 unrolled make_key_sched a bit more
 * 1.1 added norm_expand_bits
 * 1.0 First working version
 */
#include <sys/param.h>
#include <sys/systm.h>
#include <crypto/des/des_locl.h>
#include <crypto/des/podd.h>
#include <crypto/des/sk.h>

int des_check_key=0;

void des_set_odd_parity(des_cblock *key)
{
        int i;

        for (i=0; i<DES_KEY_SZ; i++)
                (*key)[i]=odd_parity[(*key)[i]];
}

int des_check_key_parity(des_cblock *key)
{
        int i;

        for (i=0; i<DES_KEY_SZ; i++)
                {
                if ((*key)[i] != odd_parity[(*key)[i]])
                        return(0);
                }
        return(1);
}

/* Weak and semi week keys as take from
 * %A D.W. Davies
 * %A W.L. Price
 * %T Security for Computer Networks
 * %I John Wiley & Sons
 * %D 1984
 * Many thanks to smb@ulysses.att.com (Steven Bellovin) for the reference
 * (and actual cblock values).
 */
#define NUM_WEAK_KEY    16
static des_cblock weak_keys[NUM_WEAK_KEY]={
        /* weak keys */
        {0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01},
        {0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE},
        {0x1F,0x1F,0x1F,0x1F,0x0E,0x0E,0x0E,0x0E},
        {0xE0,0xE0,0xE0,0xE0,0xF1,0xF1,0xF1,0xF1},
        /* semi-weak keys */
        {0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE},
        {0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01},
        {0x1F,0xE0,0x1F,0xE0,0x0E,0xF1,0x0E,0xF1},
        {0xE0,0x1F,0xE0,0x1F,0xF1,0x0E,0xF1,0x0E},
        {0x01,0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1},
        {0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1,0x01},
        {0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E,0xFE},
        {0xFE,0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E},
        {0x01,0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E},
        {0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E,0x01},
        {0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1,0xFE},
        {0xFE,0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1}};

int des_is_weak_key(des_cblock *key)
{
        int i;

        for (i=0; i<NUM_WEAK_KEY; i++)
                /* Added == 0 to comparison, I obviously don't run
                 * this section very often :-(, thanks to
                 * engineering@MorningStar.Com for the fix
                 * eay 93/06/29
                 * Another problem, I was comparing only the first 4
                 * bytes, 97/03/18 */
                if (memcmp(weak_keys[i],key,sizeof(des_cblock)) == 0) return(1);
        return(0);
}

/* NOW DEFINED IN des_local.h
 * See ecb_encrypt.c for a pseudo description of these macros. 
 * #define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\
 *      (b)^=(t),\
 *      (a)=((a)^((t)<<(n))))
 */

#define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)),\
        (a)=(a)^(t)^(t>>(16-(n))))

int des_set_key(des_cblock *key, des_key_schedule schedule)
{
        if (des_check_key)
        {
                return des_set_key_checked(key, schedule);
        }
        else
        {
                des_set_key_unchecked(key, schedule);
                return 0;
        }
}

/* return 0 if key parity is odd (correct),
 * return -1 if key parity error,
 * return -2 if illegal weak key.
 */
int des_set_key_checked(des_cblock *key, des_key_schedule schedule)
{
        if (!des_check_key_parity(key))
                return(-1);
        if (des_is_weak_key(key))
                return(-2);
        des_set_key_unchecked(key, schedule);
        return 0;
}

void des_set_key_unchecked(des_cblock *key, des_key_schedule schedule)
{
        static int shifts2[16]={0,0,1,1,1,1,1,1,0,1,1,1,1,1,1,0};
        register DES_LONG c,d,t,s,t2;
        register const unsigned char *in;
        register DES_LONG *k;
        register int i;

        k = &schedule->ks.deslong[0];
        in = &(*key)[0];

        c2l(in,c);
        c2l(in,d);

        /* do PC1 in 47 simple operations :-)
         * Thanks to John Fletcher (john_fletcher@lccmail.ocf.llnl.gov)
         * for the inspiration. :-) */
        PERM_OP (d,c,t,4,0x0f0f0f0fL);
        HPERM_OP(c,t,-2,0xcccc0000L);
        HPERM_OP(d,t,-2,0xcccc0000L);
        PERM_OP (d,c,t,1,0x55555555L);
        PERM_OP (c,d,t,8,0x00ff00ffL);
        PERM_OP (d,c,t,1,0x55555555L);
        d=      (((d&0x000000ffL)<<16L)| (d&0x0000ff00L)     |
                 ((d&0x00ff0000L)>>16L)|((c&0xf0000000L)>>4L));
        c&=0x0fffffffL;

        for (i=0; i<ITERATIONS; i++)
        {
                if (shifts2[i])
                        { c=((c>>2L)|(c<<26L)); d=((d>>2L)|(d<<26L)); }
                else
                        { c=((c>>1L)|(c<<27L)); d=((d>>1L)|(d<<27L)); }
                c&=0x0fffffffL;
                d&=0x0fffffffL;
                /* could be a few less shifts but I am to lazy at this
                * point in time to investigate */
                s=      des_skb[0][ (c    )&0x3f                ]|
                        des_skb[1][((c>> 6L)&0x03)|((c>> 7L)&0x3c)]|
                        des_skb[2][((c>>13L)&0x0f)|((c>>14L)&0x30)]|
                        des_skb[3][((c>>20L)&0x01)|((c>>21L)&0x06) |
                                                        ((c>>22L)&0x38)];
                t=      des_skb[4][ (d    )&0x3f                ]|
                        des_skb[5][((d>> 7L)&0x03)|((d>> 8L)&0x3c)]|
                        des_skb[6][ (d>>15L)&0x3f                ]|
                        des_skb[7][((d>>21L)&0x0f)|((d>>22L)&0x30)];

                /* table contained 0213 4657 */
                t2=((t<<16L)|(s&0x0000ffffL))&0xffffffffL;
                *(k++)=ROTATE(t2,30)&0xffffffffL;

                t2=((s>>16L)|(t&0xffff0000L));
                *(k++)=ROTATE(t2,26)&0xffffffffL;
        }
}

int des_key_sched(des_cblock *key, des_key_schedule schedule)
{
        return(des_set_key(key,schedule));
}

void des_fixup_key_parity(des_cblock *key)
{
        des_set_odd_parity(key);
}