OpenBSD-4.6/lib/libdes/set_key.c
/* crypto/des/set_key.c */
/* Copyright (C) 1995-1997 Eric Young (eay@mincom.oz.au)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@mincom.oz.au).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@mincom.oz.au).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library 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 cryptographic software written by
* Eric Young (eay@mincom.oz.au)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@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 "des_locl.h"
#include "podd.h"
#include "sk.h"
#ifndef _DES_NOPROTO
static int check_parity(des_cblock (*key));
#else
static int check_parity();
#endif
int des_check_key=0;
void des_set_odd_parity(key)
des_cblock (*key);
{
int i;
for (i=0; i<DES_KEY_SZ; i++)
(*key)[i]=odd_parity[(*key)[i]];
}
static int check_parity(key)
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,0x1F,0x1F,0x1F,0x1F},
{0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,0xE0},
/* 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(key)
des_cblock (*key);
{
int i;
for (i=0; i<NUM_WEAK_KEY; i++)
/* Added == 0 to comparision, I obviously don't run
* this section very often :-(, thanks to
* engineering@MorningStar.Com for the fix
* eay 93/06/29 */
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))))
/* return 0 if key parity is odd (correct),
* return -1 if key parity error,
* return -2 if illegal weak key.
*/
int des_set_key(key, schedule)
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 unsigned char *in;
register DES_LONG *k;
register int i;
if (des_check_key)
{
if (!check_parity(key))
return(-1);
if (des_is_weak_key(key))
return(-2);
}
k=(DES_LONG *)schedule;
in=(unsigned char *)key;
c2l(in,c);
c2l(in,d);
/* do PC1 in 60 simple operations */
/* PERM_OP(d,c,t,4,0x0f0f0f0fL);
HPERM_OP(c,t,-2, 0xcccc0000L);
HPERM_OP(c,t,-1, 0xaaaa0000L);
HPERM_OP(c,t, 8, 0x00ff0000L);
HPERM_OP(c,t,-1, 0xaaaa0000L);
HPERM_OP(d,t,-8, 0xff000000L);
HPERM_OP(d,t, 8, 0x00ff0000L);
HPERM_OP(d,t, 2, 0x33330000L);
d=((d&0x00aa00aaL)<<7L)|((d&0x55005500L)>>7L)|(d&0xaa55aa55L);
d=(d>>8)|((c&0xf0000000L)>>4);
c&=0x0fffffffL; */
/* I now do it 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>>2)|(c<<26)); d=((d>>2)|(d<<26)); }
else
{ c=((c>>1)|(c<<27)); d=((d>>1)|(d<<27)); }
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>> 6)&0x03)|((c>> 7)&0x3c)]|
des_skb[2][((c>>13)&0x0f)|((c>>14)&0x30)]|
des_skb[3][((c>>20)&0x01)|((c>>21)&0x06) |
((c>>22)&0x38)];
t= des_skb[4][ (d )&0x3f ]|
des_skb[5][((d>> 7)&0x03)|((d>> 8)&0x3c)]|
des_skb[6][ (d>>15)&0x3f ]|
des_skb[7][((d>>21)&0x0f)|((d>>22)&0x30)];
/* table contained 0213 4657 */
t2=((t<<16)|(s&0x0000ffffL))&0xffffffffL;
*(k++)=ROTATE(t2,30)&0xffffffffL;
t2=((s>>16)|(t&0xffff0000L));
*(k++)=ROTATE(t2,26)&0xffffffffL;
}
return(0);
}
int des_key_sched(key, schedule)
des_cblock (*key);
des_key_schedule schedule;
{
return(des_set_key(key,schedule));
}