mk_req_ext.c revision 178825 
1/*
2 * Copyright (c) 1997 - 2002 Kungliga Tekniska H�gskolan
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
36RCSID("$Id: mk_req_ext.c 19511 2006-12-27 12:07:22Z lha $");
37
38krb5_error_code
39_krb5_mk_req_internal(krb5_context context,
40		      krb5_auth_context *auth_context,
41		      const krb5_flags ap_req_options,
42		      krb5_data *in_data,
43		      krb5_creds *in_creds,
44		      krb5_data *outbuf,
45		      krb5_key_usage checksum_usage,
46		      krb5_key_usage encrypt_usage)
47{
48    krb5_error_code ret;
49    krb5_data authenticator;
50    Checksum c;
51    Checksum *c_opt;
52    krb5_auth_context ac;
53
54    if(auth_context) {
55	if(*auth_context == NULL)
56	    ret = krb5_auth_con_init(context, auth_context);
57	else
58	    ret = 0;
59	ac = *auth_context;
60    } else
61	ret = krb5_auth_con_init(context, &ac);
62    if(ret)
63	return ret;
64
65    if(ac->local_subkey == NULL && (ap_req_options & AP_OPTS_USE_SUBKEY)) {
66	ret = krb5_auth_con_generatelocalsubkey(context,
67						ac,
68						&in_creds->session);
69	if(ret)
70	    goto out;
71    }
72
73    krb5_free_keyblock(context, ac->keyblock);
74    ret = krb5_copy_keyblock(context, &in_creds->session, &ac->keyblock);
75    if (ret)
76	goto out;
77
78    /* it's unclear what type of checksum we can use.  try the best one, except:
79     * a) if it's configured differently for the current realm, or
80     * b) if the session key is des-cbc-crc
81     */
82
83    if (in_data) {
84	if(ac->keyblock->keytype == ETYPE_DES_CBC_CRC) {
85	    /* this is to make DCE secd (and older MIT kdcs?) happy */
86	    ret = krb5_create_checksum(context,
87				       NULL,
88				       0,
89				       CKSUMTYPE_RSA_MD4,
90				       in_data->data,
91				       in_data->length,
92				       &c);
93	} else if(ac->keyblock->keytype == ETYPE_ARCFOUR_HMAC_MD5 ||
94		  ac->keyblock->keytype == ETYPE_ARCFOUR_HMAC_MD5_56 ||
95		  ac->keyblock->keytype == ETYPE_DES_CBC_MD4 ||
96		  ac->keyblock->keytype == ETYPE_DES_CBC_MD5) {
97	    /* this is to make MS kdc happy */
98	    ret = krb5_create_checksum(context,
99				       NULL,
100				       0,
101				       CKSUMTYPE_RSA_MD5,
102				       in_data->data,
103				       in_data->length,
104				       &c);
105	} else {
106	    krb5_crypto crypto;
107
108	    ret = krb5_crypto_init(context, ac->keyblock, 0, &crypto);
109	    if (ret)
110		goto out;
111	    ret = krb5_create_checksum(context,
112				       crypto,
113				       checksum_usage,
114				       0,
115				       in_data->data,
116				       in_data->length,
117				       &c);
118	    krb5_crypto_destroy(context, crypto);
119	}
120	c_opt = &c;
121    } else {
122	c_opt = NULL;
123    }
124
125    if (ret)
126	goto out;
127
128    ret = krb5_build_authenticator (context,
129				    ac,
130				    ac->keyblock->keytype,
131				    in_creds,
132				    c_opt,
133				    NULL,
134				    &authenticator,
135				    encrypt_usage);
136    if (c_opt)
137	free_Checksum (c_opt);
138    if (ret)
139	goto out;
140
141    ret = krb5_build_ap_req (context, ac->keyblock->keytype,
142			     in_creds, ap_req_options, authenticator, outbuf);
143out:
144    if(auth_context == NULL)
145	krb5_auth_con_free(context, ac);
146    return ret;
147}
148
149krb5_error_code KRB5_LIB_FUNCTION
150krb5_mk_req_extended(krb5_context context,
151		     krb5_auth_context *auth_context,
152		     const krb5_flags ap_req_options,
153		     krb5_data *in_data,
154		     krb5_creds *in_creds,
155		     krb5_data *outbuf)
156{
157    return _krb5_mk_req_internal (context,
158				 auth_context,
159				 ap_req_options,
160				 in_data,
161				 in_creds,
162				 outbuf,
163				 KRB5_KU_AP_REQ_AUTH_CKSUM,
164				 KRB5_KU_AP_REQ_AUTH);
165}
166