1/*
2 * Copyright (c) 1997 - 2002 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
36krb5_error_code
37_krb5_mk_req_internal(krb5_context context,
38		      krb5_auth_context *auth_context,
39		      const krb5_flags ap_req_options,
40		      krb5_data *in_data,
41		      krb5_creds *in_creds,
42		      krb5_data *outbuf,
43		      krb5_key_usage checksum_usage,
44		      krb5_key_usage encrypt_usage)
45{
46    krb5_error_code ret;
47    krb5_data authenticator;
48    Checksum c;
49    Checksum *c_opt;
50    krb5_auth_context ac;
51
52    if(auth_context) {
53	if(*auth_context == NULL)
54	    ret = krb5_auth_con_init(context, auth_context);
55	else
56	    ret = 0;
57	ac = *auth_context;
58    } else
59	ret = krb5_auth_con_init(context, &ac);
60    if(ret)
61	return ret;
62
63    if(ac->local_subkey == NULL && (ap_req_options & AP_OPTS_USE_SUBKEY)) {
64	ret = krb5_auth_con_generatelocalsubkey(context,
65						ac,
66						&in_creds->session);
67	if(ret)
68	    goto out;
69    }
70
71    krb5_free_keyblock(context, ac->keyblock);
72    ret = krb5_copy_keyblock(context, &in_creds->session, &ac->keyblock);
73    if (ret)
74	goto out;
75
76    /* it's unclear what type of checksum we can use.  try the best one, except:
77     * a) if it's configured differently for the current realm, or
78     * b) if the session key is des-cbc-crc
79     */
80
81    if (in_data) {
82	if(ac->keyblock->keytype == ETYPE_DES_CBC_CRC) {
83	    /* this is to make DCE secd (and older MIT kdcs?) happy */
84	    ret = krb5_create_checksum(context,
85				       NULL,
86				       0,
87				       CKSUMTYPE_RSA_MD4,
88				       in_data->data,
89				       in_data->length,
90				       &c);
91	} else if(ac->keyblock->keytype == ETYPE_ARCFOUR_HMAC_MD5 ||
92		  ac->keyblock->keytype == ETYPE_ARCFOUR_HMAC_MD5_56 ||
93		  ac->keyblock->keytype == ETYPE_DES_CBC_MD4 ||
94		  ac->keyblock->keytype == ETYPE_DES_CBC_MD5) {
95	    /* this is to make MS kdc happy */
96	    ret = krb5_create_checksum(context,
97				       NULL,
98				       0,
99				       CKSUMTYPE_RSA_MD5,
100				       in_data->data,
101				       in_data->length,
102				       &c);
103	} else {
104	    krb5_crypto crypto;
105
106	    ret = krb5_crypto_init(context, ac->keyblock, 0, &crypto);
107	    if (ret)
108		goto out;
109	    ret = krb5_create_checksum(context,
110				       crypto,
111				       checksum_usage,
112				       0,
113				       in_data->data,
114				       in_data->length,
115				       &c);
116	    krb5_crypto_destroy(context, crypto);
117	}
118	c_opt = &c;
119    } else {
120	c_opt = NULL;
121    }
122
123    if (ret)
124	goto out;
125
126    ret = _krb5_build_authenticator(context,
127				    ac,
128				    ac->keyblock->keytype,
129				    in_creds,
130				    c_opt,
131				    &authenticator,
132				    encrypt_usage);
133    if (c_opt)
134	free_Checksum (c_opt);
135    if (ret)
136	goto out;
137
138    ret = krb5_build_ap_req (context, ac->keyblock->keytype,
139			     in_creds, ap_req_options, authenticator, outbuf);
140out:
141    if(auth_context == NULL)
142	krb5_auth_con_free(context, ac);
143    return ret;
144}
145
146KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
147krb5_mk_req_extended(krb5_context context,
148		     krb5_auth_context *auth_context,
149		     const krb5_flags ap_req_options,
150		     krb5_data *in_data,
151		     krb5_creds *in_creds,
152		     krb5_data *outbuf)
153{
154    return _krb5_mk_req_internal (context,
155				 auth_context,
156				 ap_req_options,
157				 in_data,
158				 in_creds,
159				 outbuf,
160				 KRB5_KU_AP_REQ_AUTH_CKSUM,
161				 KRB5_KU_AP_REQ_AUTH);
162}
163