openssl/crypto/des/str2key.c

/*
 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (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/crypto.h>
#include "des_local.h"

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

    memset(key, 0, 8);
    length = strlen(str);
    for (i = 0; i < length; i++) {
        register unsigned char 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;
        }
    }
    DES_set_odd_parity(key);
    DES_set_key_unchecked(key, &ks);
    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;

    memset(key1, 0, 8);
    memset(key2, 0, 8);
    length = strlen(str);
    for (i = 0; i < length; i++) {
        register unsigned char 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);
    DES_set_odd_parity(key1);
    DES_set_odd_parity(key2);
    DES_set_key_unchecked(key1, &ks);
    DES_cbc_cksum((const unsigned char *)str, key1, length, &ks, key1);
    DES_set_key_unchecked(key2, &ks);
    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);
}