lib/krb5/salt-aes.c

   1 /*
   2  * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "krb5_locl.h"
  35
  36 int _krb5_AES_string_to_default_iterator = 4096;
  37
  38 static krb5_error_code
  39 AES_string_to_key(krb5_context context,
  40                   krb5_enctype enctype,
  41                   krb5_data password,
  42                   krb5_salt salt,
  43                   krb5_data opaque,
  44                   krb5_keyblock *key)
  45 {
  46     krb5_error_code ret;
  47     uint32_t iter;
  48     struct _krb5_encryption_type *et;
  49     struct _krb5_key_data kd;
  50
  51     if (opaque.length == 0)
  52         iter = _krb5_AES_string_to_default_iterator;
  53     else if (opaque.length == 4) {
  54         unsigned long v;
  55         _krb5_get_int(opaque.data, &v, 4);
  56         iter = ((uint32_t)v);
  57     } else
  58         return KRB5_PROG_KEYTYPE_NOSUPP; /* XXX */
  59
  60     et = _krb5_find_enctype(enctype);
  61     if (et == NULL)
  62         return KRB5_PROG_KEYTYPE_NOSUPP;
  63
  64     kd.schedule = NULL;
  65     ALLOC(kd.key, 1);
  66     if (kd.key == NULL)
  67         return krb5_enomem(context);
  68     kd.key->keytype = enctype;
  69     ret = krb5_data_alloc(&kd.key->keyvalue, et->keytype->size);
  70     if (ret) {
  71         krb5_set_error_message (context, ret, N_("malloc: out of memory", ""));
  72         return ret;
  73     }
  74
  75     ret = PKCS5_PBKDF2_HMAC_SHA1(password.data, password.length,
  76                                  salt.saltvalue.data, salt.saltvalue.length,
  77                                  iter,
  78                                  et->keytype->size, kd.key->keyvalue.data);
  79     if (ret != 1) {
  80         _krb5_free_key_data(context, &kd, et);
  81         krb5_set_error_message(context, KRB5_PROG_KEYTYPE_NOSUPP,
  82                                "Error calculating s2k");
  83         return KRB5_PROG_KEYTYPE_NOSUPP;
  84     }
  85
  86     ret = _krb5_derive_key(context, et, &kd, "kerberos", strlen("kerberos"));
  87     if (ret == 0)
  88         ret = krb5_copy_keyblock_contents(context, kd.key, key);
  89     _krb5_free_key_data(context, &kd, et);
  90
  91     return ret;
  92 }
  93
  94 struct salt_type _krb5_AES_salt[] = {
  95     {
  96         KRB5_PW_SALT,
  97         "pw-salt",
  98         AES_string_to_key
  99     },
 100     { 0, NULL, NULL }
 101 };