xref: /freebsd/crypto/heimdal/lib/krb5/generate_subkey.c (revision af23369a6deaaeb612ab266eb88b8bb8d560c322)
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 /**
37  * Generate subkey, from keyblock
38  *
39  * @param context kerberos context
40  * @param key session key
41  * @param etype encryption type of subkey, if ETYPE_NULL, use key's enctype
42  * @param subkey returned new, free with krb5_free_keyblock().
43  *
44  * @return 0 on success or a Kerberos 5 error code
45  *
46 * @ingroup krb5_crypto
47  */
48 
49 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
50 krb5_generate_subkey_extended(krb5_context context,
51 			      const krb5_keyblock *key,
52 			      krb5_enctype etype,
53 			      krb5_keyblock **subkey)
54 {
55     krb5_error_code ret;
56 
57     ALLOC(*subkey, 1);
58     if (*subkey == NULL) {
59 	krb5_set_error_message(context, ENOMEM,N_("malloc: out of memory", ""));
60 	return ENOMEM;
61     }
62 
63     if (etype == ETYPE_NULL)
64 	etype = key->keytype; /* use session key etype */
65 
66     /* XXX should we use the session key as input to the RF? */
67     ret = krb5_generate_random_keyblock(context, etype, *subkey);
68     if (ret != 0) {
69 	free(*subkey);
70 	*subkey = NULL;
71     }
72 
73     return ret;
74 }
75 
76