xref: /freebsd/crypto/heimdal/lib/krb5/mk_req_ext.c (revision b9f654b163bce26de79705e77b872427c9f2afa1)
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 
36 krb5_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);
140 out:
141     if(auth_context == NULL)
142 	krb5_auth_con_free(context, ac);
143     return ret;
144 }
145 
146 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
147 krb5_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