c_skey.c
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/*
* Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <openssl/cast.h>
#include "cast_lcl.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;
}
}