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2023-09-03 18:24:16 -07:00
/* $OpenBSD: c_skey.c,v 1.14 2023/07/08 10:43:59 beck Exp $ */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* 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@cryptsoft.com).
*
* 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@cryptsoft.com)"
* 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@cryptsoft.com)"
*
* 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.]
*/
#include <openssl/crypto.h>
#include <openssl/cast.h>
#include "cast_local.h"
#include "cast_s.h"
#define CAST_exp(l,A,a,n) \
A[n/4]=l; \
a[n+3]=(l )&0xff; \
a[n+2]=(l>> 8)&0xff; \
a[n+1]=(l>>16)&0xff; \
a[n+0]=(l>>24)&0xff;
#define S4 CAST_S_table4
#define S5 CAST_S_table5
#define S6 CAST_S_table6
#define S7 CAST_S_table7
void
CAST_set_key(CAST_KEY *key, int len, const unsigned char *data)
{
CAST_LONG x[16];
CAST_LONG z[16];
CAST_LONG k[32];
CAST_LONG X[4], Z[4];
CAST_LONG l, *K;
int i;
for (i = 0;
i < 16;
i++) x[i] = 0;
if (len > 16)
len = 16;
for (i = 0; i < len; i++)
x[i] = data[i];
if (len <= 10)
key->short_key = 1;
else
key->short_key = 0;
K = &k[0];
X[0] = ((x[ 0]<<24)|(x[ 1]<<16)|(x[ 2]<<8)|x[ 3])&0xffffffffL;
X[1] = ((x[ 4]<<24)|(x[ 5]<<16)|(x[ 6]<<8)|x[ 7])&0xffffffffL;
X[2] = ((x[ 8]<<24)|(x[ 9]<<16)|(x[10]<<8)|x[11])&0xffffffffL;
X[3] = ((x[12]<<24)|(x[13]<<16)|(x[14]<<8)|x[15])&0xffffffffL;
for (;;) {
l = X[0]^S4[x[13]]^S5[x[15]]^S6[x[12]]^S7[x[14]]^S6[x[ 8]];
CAST_exp(l, Z, z, 0);
l = X[2]^S4[z[ 0]]^S5[z[ 2]]^S6[z[ 1]]^S7[z[ 3]]^S7[x[10]];
CAST_exp(l, Z, z, 4);
l = X[3]^S4[z[ 7]]^S5[z[ 6]]^S6[z[ 5]]^S7[z[ 4]]^S4[x[ 9]];
CAST_exp(l, Z, z, 8);
l = X[1]^S4[z[10]]^S5[z[ 9]]^S6[z[11]]^S7[z[ 8]]^S5[x[11]];
CAST_exp(l, Z,z, 12);
K[0] = S4[z[ 8]]^S5[z[ 9]]^S6[z[ 7]]^S7[z[ 6]]^S4[z[ 2]];
K[1] = S4[z[10]]^S5[z[11]]^S6[z[ 5]]^S7[z[ 4]]^S5[z[ 6]];
K[2] = S4[z[12]]^S5[z[13]]^S6[z[ 3]]^S7[z[ 2]]^S6[z[ 9]];
K[3] = S4[z[14]]^S5[z[15]]^S6[z[ 1]]^S7[z[ 0]]^S7[z[12]];
l = Z[2]^S4[z[ 5]]^S5[z[ 7]]^S6[z[ 4]]^S7[z[ 6]]^S6[z[ 0]];
CAST_exp(l, X, x, 0);
l = Z[0]^S4[x[ 0]]^S5[x[ 2]]^S6[x[ 1]]^S7[x[ 3]]^S7[z[ 2]];
CAST_exp(l, X, x, 4);
l = Z[1]^S4[x[ 7]]^S5[x[ 6]]^S6[x[ 5]]^S7[x[ 4]]^S4[z[ 1]];
CAST_exp(l, X, x, 8);
l = Z[3]^S4[x[10]]^S5[x[ 9]]^S6[x[11]]^S7[x[ 8]]^S5[z[ 3]];
CAST_exp(l, X,x, 12);
K[4] = S4[x[ 3]]^S5[x[ 2]]^S6[x[12]]^S7[x[13]]^S4[x[ 8]];
K[5] = S4[x[ 1]]^S5[x[ 0]]^S6[x[14]]^S7[x[15]]^S5[x[13]];
K[6] = S4[x[ 7]]^S5[x[ 6]]^S6[x[ 8]]^S7[x[ 9]]^S6[x[ 3]];
K[7] = S4[x[ 5]]^S5[x[ 4]]^S6[x[10]]^S7[x[11]]^S7[x[ 7]];
l = X[0]^S4[x[13]]^S5[x[15]]^S6[x[12]]^S7[x[14]]^S6[x[ 8]];
CAST_exp(l, Z, z, 0);
l = X[2]^S4[z[ 0]]^S5[z[ 2]]^S6[z[ 1]]^S7[z[ 3]]^S7[x[10]];
CAST_exp(l, Z, z, 4);
l = X[3]^S4[z[ 7]]^S5[z[ 6]]^S6[z[ 5]]^S7[z[ 4]]^S4[x[ 9]];
CAST_exp(l, Z, z, 8);
l = X[1]^S4[z[10]]^S5[z[ 9]]^S6[z[11]]^S7[z[ 8]]^S5[x[11]];
CAST_exp(l, Z,z, 12);
K[8] = S4[z[ 3]]^S5[z[ 2]]^S6[z[12]]^S7[z[13]]^S4[z[ 9]];
K[9] = S4[z[ 1]]^S5[z[ 0]]^S6[z[14]]^S7[z[15]]^S5[z[12]];
K[10] = S4[z[ 7]]^S5[z[ 6]]^S6[z[ 8]]^S7[z[ 9]]^S6[z[ 2]];
K[11] = S4[z[ 5]]^S5[z[ 4]]^S6[z[10]]^S7[z[11]]^S7[z[ 6]];
l = Z[2]^S4[z[ 5]]^S5[z[ 7]]^S6[z[ 4]]^S7[z[ 6]]^S6[z[ 0]];
CAST_exp(l, X, x, 0);
l = Z[0]^S4[x[ 0]]^S5[x[ 2]]^S6[x[ 1]]^S7[x[ 3]]^S7[z[ 2]];
CAST_exp(l, X, x, 4);
l = Z[1]^S4[x[ 7]]^S5[x[ 6]]^S6[x[ 5]]^S7[x[ 4]]^S4[z[ 1]];
CAST_exp(l, X, x, 8);
l = Z[3]^S4[x[10]]^S5[x[ 9]]^S6[x[11]]^S7[x[ 8]]^S5[z[ 3]];
CAST_exp(l, X,x, 12);
K[12] = S4[x[ 8]]^S5[x[ 9]]^S6[x[ 7]]^S7[x[ 6]]^S4[x[ 3]];
K[13] = S4[x[10]]^S5[x[11]]^S6[x[ 5]]^S7[x[ 4]]^S5[x[ 7]];
K[14] = S4[x[12]]^S5[x[13]]^S6[x[ 3]]^S7[x[ 2]]^S6[x[ 8]];
K[15] = S4[x[14]]^S5[x[15]]^S6[x[ 1]]^S7[x[ 0]]^S7[x[13]];
if (K != k)
break;
K += 16;
}
for (i = 0; i < 16; i++) {
key->data[i*2] = k[i];
key->data[i*2 + 1] = ((k[i + 16]) + 16)&0x1f;
}
}
LCRYPTO_ALIAS(CAST_set_key);