/*
 * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
 * (Royal Institute of Technology, Stockholm, Sweden).
 * All rights reserved.
 *
 * 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 above 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. Neither the name of the Institute nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``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 INSTITUTE 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.
 */

#include "krb5_locl.h"

#ifdef DES3_OLD_ENCTYPE
static krb5_error_code
DES3_string_to_key(krb5_context context,
                   krb5_enctype enctype,
                   krb5_data password,
                   krb5_salt salt,
                   krb5_data opaque,
                   krb5_keyblock *key)
{
    char *str;
    size_t len;
    unsigned char tmp[24];
    DES_cblock keys[3];
    krb5_error_code ret;

    len = password.length + salt.saltvalue.length;
    str = malloc(len);
    if(len != 0 && str == NULL) {
        krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
        return ENOMEM;
    }
    memcpy(str, password.data, password.length);
    memcpy(str + password.length, salt.saltvalue.data, salt.saltvalue.length);
    {
        DES_cblock ivec;
        DES_key_schedule s[3];
        int i;

        ret = _krb5_n_fold(str, len, tmp, 24);
        if (ret) {
            memset(str, 0, len);
            free(str);
            krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
            return ret;
        }

        for(i = 0; i < 3; i++){
            memcpy(keys + i, tmp + i * 8, sizeof(keys[i]));
            DES_set_odd_parity(keys + i);
            if(DES_is_weak_key(keys + i))
                _krb5_xor(keys + i, (const unsigned char*)"\0\0\0\0\0\0\0\xf0");
            DES_set_key_unchecked(keys + i, &s[i]);
        }
        memset(&ivec, 0, sizeof(ivec));
        DES_ede3_cbc_encrypt(tmp,
                             tmp, sizeof(tmp),
                             &s[0], &s[1], &s[2], &ivec, DES_ENCRYPT);
        memset(s, 0, sizeof(s));
        memset(&ivec, 0, sizeof(ivec));
        for(i = 0; i < 3; i++){
            memcpy(keys + i, tmp + i * 8, sizeof(keys[i]));
            DES_set_odd_parity(keys + i);
            if(DES_is_weak_key(keys + i))
                _krb5_xor(keys + i, (const unsigned char*)"\0\0\0\0\0\0\0\xf0");
        }
        memset(tmp, 0, sizeof(tmp));
    }
    key->keytype = enctype;
    krb5_data_copy(&key->keyvalue, keys, sizeof(keys));
    memset(keys, 0, sizeof(keys));
    memset(str, 0, len);
    free(str);
    return 0;
}
#endif

static krb5_error_code
DES3_string_to_key_derived(krb5_context context,
                           krb5_enctype enctype,
                           krb5_data password,
                           krb5_salt salt,
                           krb5_data opaque,
                           krb5_keyblock *key)
{
    krb5_error_code ret;
    size_t len = password.length + salt.saltvalue.length;
    char *s;

    s = malloc(len);
    if(len != 0 && s == NULL) {
        krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
        return ENOMEM;
    }
    memcpy(s, password.data, password.length);
    memcpy(s + password.length, salt.saltvalue.data, salt.saltvalue.length);
    ret = krb5_string_to_key_derived(context,
                                     s,
                                     len,
                                     enctype,
                                     key);
    memset(s, 0, len);
    free(s);
    return ret;
}


#ifdef DES3_OLD_ENCTYPE
struct salt_type _krb5_des3_salt[] = {
    {
        KRB5_PW_SALT,
        "pw-salt",
        DES3_string_to_key
    },
    { 0 }
};
#endif

struct salt_type _krb5_des3_salt_derived[] = {
    {
        KRB5_PW_SALT,
        "pw-salt",
        DES3_string_to_key_derived
    },
    { 0 }
};