source-engine/thirdparty/openssl/crypto/des/str2key.c

/* crypto/des/str2key.c */
/* 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 "des_locl.h"

void DES_string_to_key(const char *str, DES_cblock *key)
{
    DES_key_schedule ks;
    int i, length;
    register unsigned char j;

    memset(key, 0, 8);
    length = strlen(str);
#ifdef OLD_STR_TO_KEY
    for (i = 0; i < length; i++)
        (*key)[i % 8] ^= (str[i] << 1);
#else                           /* MIT COMPATIBLE */
    for (i = 0; i < length; i++) {
        j = str[i];
        if ((i % 16) < 8)
            (*key)[i % 8] ^= (j << 1);
        else {
            /* Reverse the bit order 05/05/92 eay */
            j = ((j << 4) & 0xf0) | ((j >> 4) & 0x0f);
            j = ((j << 2) & 0xcc) | ((j >> 2) & 0x33);
            j = ((j << 1) & 0xaa) | ((j >> 1) & 0x55);
            (*key)[7 - (i % 8)] ^= j;
        }
    }
#endif
    DES_set_odd_parity(key);
#ifdef EXPERIMENTAL_STR_TO_STRONG_KEY
    if (DES_is_weak_key(key))
        (*key)[7] ^= 0xF0;
    DES_set_key(key, &ks);
#else
    DES_set_key_unchecked(key, &ks);
#endif
    DES_cbc_cksum((const unsigned char *)str, key, length, &ks, key);
    OPENSSL_cleanse(&ks, sizeof(ks));
    DES_set_odd_parity(key);
}

void DES_string_to_2keys(const char *str, DES_cblock *key1, DES_cblock *key2)
{
    DES_key_schedule ks;
    int i, length;
    register unsigned char j;

    memset(key1, 0, 8);
    memset(key2, 0, 8);
    length = strlen(str);
#ifdef OLD_STR_TO_KEY
    if (length <= 8) {
        for (i = 0; i < length; i++) {
            (*key2)[i] = (*key1)[i] = (str[i] << 1);
        }
    } else {
        for (i = 0; i < length; i++) {
            if ((i / 8) & 1)
                (*key2)[i % 8] ^= (str[i] << 1);
            else
                (*key1)[i % 8] ^= (str[i] << 1);
        }
    }
#else                           /* MIT COMPATIBLE */
    for (i = 0; i < length; i++) {
        j = str[i];
        if ((i % 32) < 16) {
            if ((i % 16) < 8)
                (*key1)[i % 8] ^= (j << 1);
            else
                (*key2)[i % 8] ^= (j << 1);
        } else {
            j = ((j << 4) & 0xf0) | ((j >> 4) & 0x0f);
            j = ((j << 2) & 0xcc) | ((j >> 2) & 0x33);
            j = ((j << 1) & 0xaa) | ((j >> 1) & 0x55);
            if ((i % 16) < 8)
                (*key1)[7 - (i % 8)] ^= j;
            else
                (*key2)[7 - (i % 8)] ^= j;
        }
    }
    if (length <= 8)
        memcpy(key2, key1, 8);
#endif
    DES_set_odd_parity(key1);
    DES_set_odd_parity(key2);
#ifdef EXPERIMENTAL_STR_TO_STRONG_KEY
    if (DES_is_weak_key(key1))
        (*key1)[7] ^= 0xF0;
    DES_set_key(key1, &ks);
#else
    DES_set_key_unchecked(key1, &ks);
#endif
    DES_cbc_cksum((const unsigned char *)str, key1, length, &ks, key1);
#ifdef EXPERIMENTAL_STR_TO_STRONG_KEY
    if (DES_is_weak_key(key2))
        (*key2)[7] ^= 0xF0;
    DES_set_key(key2, &ks);
#else
    DES_set_key_unchecked(key2, &ks);
#endif
    DES_cbc_cksum((const unsigned char *)str, key2, length, &ks, key2);
    OPENSSL_cleanse(&ks, sizeof(ks));
    DES_set_odd_parity(key1);
    DES_set_odd_parity(key2);
}