xref: /freebsd/crypto/heimdal/lib/gssapi/krb5/8003.c (revision c19800e8cd5640693f36f2040db4ab5e8d738146)
1c19800e8SDoug Rabson /*
2c19800e8SDoug Rabson  * Copyright (c) 1997 - 2003 Kungliga Tekniska H�gskolan
3c19800e8SDoug Rabson  * (Royal Institute of Technology, Stockholm, Sweden).
4c19800e8SDoug Rabson  * All rights reserved.
5c19800e8SDoug Rabson  *
6c19800e8SDoug Rabson  * Redistribution and use in source and binary forms, with or without
7c19800e8SDoug Rabson  * modification, are permitted provided that the following conditions
8c19800e8SDoug Rabson  * are met:
9c19800e8SDoug Rabson  *
10c19800e8SDoug Rabson  * 1. Redistributions of source code must retain the above copyright
11c19800e8SDoug Rabson  *    notice, this list of conditions and the following disclaimer.
12c19800e8SDoug Rabson  *
13c19800e8SDoug Rabson  * 2. Redistributions in binary form must reproduce the above copyright
14c19800e8SDoug Rabson  *    notice, this list of conditions and the following disclaimer in the
15c19800e8SDoug Rabson  *    documentation and/or other materials provided with the distribution.
16c19800e8SDoug Rabson  *
17c19800e8SDoug Rabson  * 3. Neither the name of the Institute nor the names of its contributors
18c19800e8SDoug Rabson  *    may be used to endorse or promote products derived from this software
19c19800e8SDoug Rabson  *    without specific prior written permission.
20c19800e8SDoug Rabson  *
21c19800e8SDoug Rabson  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22c19800e8SDoug Rabson  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23c19800e8SDoug Rabson  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24c19800e8SDoug Rabson  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25c19800e8SDoug Rabson  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26c19800e8SDoug Rabson  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27c19800e8SDoug Rabson  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28c19800e8SDoug Rabson  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29c19800e8SDoug Rabson  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30c19800e8SDoug Rabson  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31c19800e8SDoug Rabson  * SUCH DAMAGE.
32c19800e8SDoug Rabson  */
33c19800e8SDoug Rabson 
34c19800e8SDoug Rabson #include "krb5/gsskrb5_locl.h"
35c19800e8SDoug Rabson 
36c19800e8SDoug Rabson RCSID("$Id: 8003.c 18334 2006-10-07 22:16:04Z lha $");
37c19800e8SDoug Rabson 
38c19800e8SDoug Rabson krb5_error_code
39c19800e8SDoug Rabson _gsskrb5_encode_om_uint32(OM_uint32 n, u_char *p)
40c19800e8SDoug Rabson {
41c19800e8SDoug Rabson   p[0] = (n >> 0)  & 0xFF;
42c19800e8SDoug Rabson   p[1] = (n >> 8)  & 0xFF;
43c19800e8SDoug Rabson   p[2] = (n >> 16) & 0xFF;
44c19800e8SDoug Rabson   p[3] = (n >> 24) & 0xFF;
45c19800e8SDoug Rabson   return 0;
46c19800e8SDoug Rabson }
47c19800e8SDoug Rabson 
48c19800e8SDoug Rabson krb5_error_code
49c19800e8SDoug Rabson _gsskrb5_encode_be_om_uint32(OM_uint32 n, u_char *p)
50c19800e8SDoug Rabson {
51c19800e8SDoug Rabson   p[0] = (n >> 24) & 0xFF;
52c19800e8SDoug Rabson   p[1] = (n >> 16) & 0xFF;
53c19800e8SDoug Rabson   p[2] = (n >> 8)  & 0xFF;
54c19800e8SDoug Rabson   p[3] = (n >> 0)  & 0xFF;
55c19800e8SDoug Rabson   return 0;
56c19800e8SDoug Rabson }
57c19800e8SDoug Rabson 
58c19800e8SDoug Rabson krb5_error_code
59c19800e8SDoug Rabson _gsskrb5_decode_om_uint32(const void *ptr, OM_uint32 *n)
60c19800e8SDoug Rabson {
61c19800e8SDoug Rabson     const u_char *p = ptr;
62c19800e8SDoug Rabson     *n = (p[0] << 0) | (p[1] << 8) | (p[2] << 16) | (p[3] << 24);
63c19800e8SDoug Rabson     return 0;
64c19800e8SDoug Rabson }
65c19800e8SDoug Rabson 
66c19800e8SDoug Rabson krb5_error_code
67c19800e8SDoug Rabson _gsskrb5_decode_be_om_uint32(const void *ptr, OM_uint32 *n)
68c19800e8SDoug Rabson {
69c19800e8SDoug Rabson     const u_char *p = ptr;
70c19800e8SDoug Rabson     *n = (p[0] <<24) | (p[1] << 16) | (p[2] << 8) | (p[3] << 0);
71c19800e8SDoug Rabson     return 0;
72c19800e8SDoug Rabson }
73c19800e8SDoug Rabson 
74c19800e8SDoug Rabson static krb5_error_code
75c19800e8SDoug Rabson hash_input_chan_bindings (const gss_channel_bindings_t b,
76c19800e8SDoug Rabson 			  u_char *p)
77c19800e8SDoug Rabson {
78c19800e8SDoug Rabson   u_char num[4];
79c19800e8SDoug Rabson   MD5_CTX md5;
80c19800e8SDoug Rabson 
81c19800e8SDoug Rabson   MD5_Init(&md5);
82c19800e8SDoug Rabson   _gsskrb5_encode_om_uint32 (b->initiator_addrtype, num);
83c19800e8SDoug Rabson   MD5_Update (&md5, num, sizeof(num));
84c19800e8SDoug Rabson   _gsskrb5_encode_om_uint32 (b->initiator_address.length, num);
85c19800e8SDoug Rabson   MD5_Update (&md5, num, sizeof(num));
86c19800e8SDoug Rabson   if (b->initiator_address.length)
87c19800e8SDoug Rabson     MD5_Update (&md5,
88c19800e8SDoug Rabson 		b->initiator_address.value,
89c19800e8SDoug Rabson 		b->initiator_address.length);
90c19800e8SDoug Rabson   _gsskrb5_encode_om_uint32 (b->acceptor_addrtype, num);
91c19800e8SDoug Rabson   MD5_Update (&md5, num, sizeof(num));
92c19800e8SDoug Rabson   _gsskrb5_encode_om_uint32 (b->acceptor_address.length, num);
93c19800e8SDoug Rabson   MD5_Update (&md5, num, sizeof(num));
94c19800e8SDoug Rabson   if (b->acceptor_address.length)
95c19800e8SDoug Rabson     MD5_Update (&md5,
96c19800e8SDoug Rabson 		b->acceptor_address.value,
97c19800e8SDoug Rabson 		b->acceptor_address.length);
98c19800e8SDoug Rabson   _gsskrb5_encode_om_uint32 (b->application_data.length, num);
99c19800e8SDoug Rabson   MD5_Update (&md5, num, sizeof(num));
100c19800e8SDoug Rabson   if (b->application_data.length)
101c19800e8SDoug Rabson     MD5_Update (&md5,
102c19800e8SDoug Rabson 		b->application_data.value,
103c19800e8SDoug Rabson 		b->application_data.length);
104c19800e8SDoug Rabson   MD5_Final (p, &md5);
105c19800e8SDoug Rabson   return 0;
106c19800e8SDoug Rabson }
107c19800e8SDoug Rabson 
108c19800e8SDoug Rabson /*
109c19800e8SDoug Rabson  * create a checksum over the chanel bindings in
110c19800e8SDoug Rabson  * `input_chan_bindings', `flags' and `fwd_data' and return it in
111c19800e8SDoug Rabson  * `result'
112c19800e8SDoug Rabson  */
113c19800e8SDoug Rabson 
114c19800e8SDoug Rabson OM_uint32
115c19800e8SDoug Rabson _gsskrb5_create_8003_checksum (
116c19800e8SDoug Rabson 		      OM_uint32 *minor_status,
117c19800e8SDoug Rabson 		      const gss_channel_bindings_t input_chan_bindings,
118c19800e8SDoug Rabson 		      OM_uint32 flags,
119c19800e8SDoug Rabson 		      const krb5_data *fwd_data,
120c19800e8SDoug Rabson 		      Checksum *result)
121c19800e8SDoug Rabson {
122c19800e8SDoug Rabson     u_char *p;
123c19800e8SDoug Rabson 
124c19800e8SDoug Rabson     /*
125c19800e8SDoug Rabson      * see rfc1964 (section 1.1.1 (Initial Token), and the checksum value
126c19800e8SDoug Rabson      * field's format) */
127c19800e8SDoug Rabson     result->cksumtype = CKSUMTYPE_GSSAPI;
128c19800e8SDoug Rabson     if (fwd_data->length > 0 && (flags & GSS_C_DELEG_FLAG))
129c19800e8SDoug Rabson 	result->checksum.length = 24 + 4 + fwd_data->length;
130c19800e8SDoug Rabson     else
131c19800e8SDoug Rabson 	result->checksum.length = 24;
132c19800e8SDoug Rabson     result->checksum.data   = malloc (result->checksum.length);
133c19800e8SDoug Rabson     if (result->checksum.data == NULL) {
134c19800e8SDoug Rabson 	*minor_status = ENOMEM;
135c19800e8SDoug Rabson 	return GSS_S_FAILURE;
136c19800e8SDoug Rabson     }
137c19800e8SDoug Rabson 
138c19800e8SDoug Rabson     p = result->checksum.data;
139c19800e8SDoug Rabson     _gsskrb5_encode_om_uint32 (16, p);
140c19800e8SDoug Rabson     p += 4;
141c19800e8SDoug Rabson     if (input_chan_bindings == GSS_C_NO_CHANNEL_BINDINGS) {
142c19800e8SDoug Rabson 	memset (p, 0, 16);
143c19800e8SDoug Rabson     } else {
144c19800e8SDoug Rabson 	hash_input_chan_bindings (input_chan_bindings, p);
145c19800e8SDoug Rabson     }
146c19800e8SDoug Rabson     p += 16;
147c19800e8SDoug Rabson     _gsskrb5_encode_om_uint32 (flags, p);
148c19800e8SDoug Rabson     p += 4;
149c19800e8SDoug Rabson 
150c19800e8SDoug Rabson     if (fwd_data->length > 0 && (flags & GSS_C_DELEG_FLAG)) {
151c19800e8SDoug Rabson 
152c19800e8SDoug Rabson 	*p++ = (1 >> 0) & 0xFF;                   /* DlgOpt */ /* == 1 */
153c19800e8SDoug Rabson 	*p++ = (1 >> 8) & 0xFF;                   /* DlgOpt */ /* == 0 */
154c19800e8SDoug Rabson 	*p++ = (fwd_data->length >> 0) & 0xFF;    /* Dlgth  */
155c19800e8SDoug Rabson 	*p++ = (fwd_data->length >> 8) & 0xFF;    /* Dlgth  */
156c19800e8SDoug Rabson 	memcpy(p, (unsigned char *) fwd_data->data, fwd_data->length);
157c19800e8SDoug Rabson 
158c19800e8SDoug Rabson 	p += fwd_data->length;
159c19800e8SDoug Rabson     }
160c19800e8SDoug Rabson 
161c19800e8SDoug Rabson     return GSS_S_COMPLETE;
162c19800e8SDoug Rabson }
163c19800e8SDoug Rabson 
164c19800e8SDoug Rabson /*
165c19800e8SDoug Rabson  * verify the checksum in `cksum' over `input_chan_bindings'
166c19800e8SDoug Rabson  * returning  `flags' and `fwd_data'
167c19800e8SDoug Rabson  */
168c19800e8SDoug Rabson 
169c19800e8SDoug Rabson OM_uint32
170c19800e8SDoug Rabson _gsskrb5_verify_8003_checksum(
171c19800e8SDoug Rabson 		      OM_uint32 *minor_status,
172c19800e8SDoug Rabson 		      const gss_channel_bindings_t input_chan_bindings,
173c19800e8SDoug Rabson 		      const Checksum *cksum,
174c19800e8SDoug Rabson 		      OM_uint32 *flags,
175c19800e8SDoug Rabson 		      krb5_data *fwd_data)
176c19800e8SDoug Rabson {
177c19800e8SDoug Rabson     unsigned char hash[16];
178c19800e8SDoug Rabson     unsigned char *p;
179c19800e8SDoug Rabson     OM_uint32 length;
180c19800e8SDoug Rabson     int DlgOpt;
181c19800e8SDoug Rabson     static unsigned char zeros[16];
182c19800e8SDoug Rabson 
183c19800e8SDoug Rabson     if (cksum == NULL) {
184c19800e8SDoug Rabson 	*minor_status = 0;
185c19800e8SDoug Rabson 	return GSS_S_BAD_BINDINGS;
186c19800e8SDoug Rabson     }
187c19800e8SDoug Rabson 
188c19800e8SDoug Rabson     /* XXX should handle checksums > 24 bytes */
189c19800e8SDoug Rabson     if(cksum->cksumtype != CKSUMTYPE_GSSAPI || cksum->checksum.length < 24) {
190c19800e8SDoug Rabson 	*minor_status = 0;
191c19800e8SDoug Rabson 	return GSS_S_BAD_BINDINGS;
192c19800e8SDoug Rabson     }
193c19800e8SDoug Rabson 
194c19800e8SDoug Rabson     p = cksum->checksum.data;
195c19800e8SDoug Rabson     _gsskrb5_decode_om_uint32(p, &length);
196c19800e8SDoug Rabson     if(length != sizeof(hash)) {
197c19800e8SDoug Rabson 	*minor_status = 0;
198c19800e8SDoug Rabson 	return GSS_S_BAD_BINDINGS;
199c19800e8SDoug Rabson     }
200c19800e8SDoug Rabson 
201c19800e8SDoug Rabson     p += 4;
202c19800e8SDoug Rabson 
203c19800e8SDoug Rabson     if (input_chan_bindings != GSS_C_NO_CHANNEL_BINDINGS
204c19800e8SDoug Rabson 	&& memcmp(p, zeros, sizeof(zeros)) != 0) {
205c19800e8SDoug Rabson 	if(hash_input_chan_bindings(input_chan_bindings, hash) != 0) {
206c19800e8SDoug Rabson 	    *minor_status = 0;
207c19800e8SDoug Rabson 	    return GSS_S_BAD_BINDINGS;
208c19800e8SDoug Rabson 	}
209c19800e8SDoug Rabson 	if(memcmp(hash, p, sizeof(hash)) != 0) {
210c19800e8SDoug Rabson 	    *minor_status = 0;
211c19800e8SDoug Rabson 	    return GSS_S_BAD_BINDINGS;
212c19800e8SDoug Rabson 	}
213c19800e8SDoug Rabson     }
214c19800e8SDoug Rabson 
215c19800e8SDoug Rabson     p += sizeof(hash);
216c19800e8SDoug Rabson 
217c19800e8SDoug Rabson     _gsskrb5_decode_om_uint32(p, flags);
218c19800e8SDoug Rabson     p += 4;
219c19800e8SDoug Rabson 
220c19800e8SDoug Rabson     if (cksum->checksum.length > 24 && (*flags & GSS_C_DELEG_FLAG)) {
221c19800e8SDoug Rabson 	if(cksum->checksum.length < 28) {
222c19800e8SDoug Rabson 	    *minor_status = 0;
223c19800e8SDoug Rabson 	    return GSS_S_BAD_BINDINGS;
224c19800e8SDoug Rabson 	}
225c19800e8SDoug Rabson 
226c19800e8SDoug Rabson 	DlgOpt = (p[0] << 0) | (p[1] << 8);
227c19800e8SDoug Rabson 	p += 2;
228c19800e8SDoug Rabson 	if (DlgOpt != 1) {
229c19800e8SDoug Rabson 	    *minor_status = 0;
230c19800e8SDoug Rabson 	    return GSS_S_BAD_BINDINGS;
231c19800e8SDoug Rabson 	}
232c19800e8SDoug Rabson 
233c19800e8SDoug Rabson 	fwd_data->length = (p[0] << 0) | (p[1] << 8);
234c19800e8SDoug Rabson 	p += 2;
235c19800e8SDoug Rabson 	if(cksum->checksum.length < 28 + fwd_data->length) {
236c19800e8SDoug Rabson 	    *minor_status = 0;
237c19800e8SDoug Rabson 	    return GSS_S_BAD_BINDINGS;
238c19800e8SDoug Rabson 	}
239c19800e8SDoug Rabson 	fwd_data->data = malloc(fwd_data->length);
240c19800e8SDoug Rabson 	if (fwd_data->data == NULL) {
241c19800e8SDoug Rabson 	    *minor_status = ENOMEM;
242c19800e8SDoug Rabson 	    return GSS_S_FAILURE;
243c19800e8SDoug Rabson 	}
244c19800e8SDoug Rabson 	memcpy(fwd_data->data, p, fwd_data->length);
245c19800e8SDoug Rabson     }
246c19800e8SDoug Rabson 
247c19800e8SDoug Rabson     return GSS_S_COMPLETE;
248c19800e8SDoug Rabson }
249