lib/krb5/generate_subkey.c

   1 /*
   2  * Copyright (c) 1997 - 2001 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 RCSID("$Id$");
  37
  38 krb5_error_code KRB5_LIB_FUNCTION
  39 krb5_generate_subkey(krb5_context context,
  40                      const krb5_keyblock *key,
  41                      krb5_keyblock **subkey)
  42 {
  43     return krb5_generate_subkey_extended(context, key, key->keytype, subkey);
  44 }
  45
  46 krb5_error_code KRB5_LIB_FUNCTION
  47 krb5_generate_subkey_extended(krb5_context context,
  48                               const krb5_keyblock *key,
  49                               krb5_enctype etype,
  50                               krb5_keyblock **subkey)
  51 {
  52     krb5_error_code ret;
  53
  54     ALLOC(*subkey, 1);
  55     if (*subkey == NULL) {
  56         krb5_set_error_string(context, "malloc: out of memory");
  57         return ENOMEM;
  58     }
  59
  60     if (etype == ETYPE_NULL)
  61         etype = key->keytype; /* use session key etype */
  62
  63     /* XXX should we use the session key as input to the RF? */
  64     ret = krb5_generate_random_keyblock(context, etype, *subkey);
  65     if (ret != 0) {
  66         free(*subkey);
  67         *subkey = NULL;
  68     }
  69
  70     return ret;
  71 }
  72