xref: /freebsd/crypto/heimdal/lib/gssapi/krb5/encapsulate.c (revision 7aa383846770374466b1dcb2cefd71bde9acf463)
1 /*
2  * Copyright (c) 1997 - 2003 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/gsskrb5_locl.h"
35 
36 RCSID("$Id: encapsulate.c 18459 2006-10-14 10:12:16Z lha $");
37 
38 void
39 _gssapi_encap_length (size_t data_len,
40 		      size_t *len,
41 		      size_t *total_len,
42 		      const gss_OID mech)
43 {
44     size_t len_len;
45 
46     *len = 1 + 1 + mech->length + data_len;
47 
48     len_len = der_length_len(*len);
49 
50     *total_len = 1 + len_len + *len;
51 }
52 
53 void
54 _gsskrb5_encap_length (size_t data_len,
55 			  size_t *len,
56 			  size_t *total_len,
57 			  const gss_OID mech)
58 {
59     _gssapi_encap_length(data_len + 2, len, total_len, mech);
60 }
61 
62 void *
63 _gsskrb5_make_header (void *ptr,
64 			 size_t len,
65 			 const void *type,
66 			 const gss_OID mech)
67 {
68     u_char *p = ptr;
69     p = _gssapi_make_mech_header(p, len, mech);
70     memcpy (p, type, 2);
71     p += 2;
72     return p;
73 }
74 
75 void *
76 _gssapi_make_mech_header(void *ptr,
77 			 size_t len,
78 			 const gss_OID mech)
79 {
80     u_char *p = ptr;
81     int e;
82     size_t len_len, foo;
83 
84     *p++ = 0x60;
85     len_len = der_length_len(len);
86     e = der_put_length (p + len_len - 1, len_len, len, &foo);
87     if(e || foo != len_len)
88 	abort ();
89     p += len_len;
90     *p++ = 0x06;
91     *p++ = mech->length;
92     memcpy (p, mech->elements, mech->length);
93     p += mech->length;
94     return p;
95 }
96 
97 /*
98  * Give it a krb5_data and it will encapsulate with extra GSS-API wrappings.
99  */
100 
101 OM_uint32
102 _gssapi_encapsulate(
103     OM_uint32 *minor_status,
104     const krb5_data *in_data,
105     gss_buffer_t output_token,
106     const gss_OID mech
107 )
108 {
109     size_t len, outer_len;
110     void *p;
111 
112     _gssapi_encap_length (in_data->length, &len, &outer_len, mech);
113 
114     output_token->length = outer_len;
115     output_token->value  = malloc (outer_len);
116     if (output_token->value == NULL) {
117 	*minor_status = ENOMEM;
118 	return GSS_S_FAILURE;
119     }
120 
121     p = _gssapi_make_mech_header (output_token->value, len, mech);
122     memcpy (p, in_data->data, in_data->length);
123     return GSS_S_COMPLETE;
124 }
125 
126 /*
127  * Give it a krb5_data and it will encapsulate with extra GSS-API krb5
128  * wrappings.
129  */
130 
131 OM_uint32
132 _gsskrb5_encapsulate(
133 			OM_uint32 *minor_status,
134 			const krb5_data *in_data,
135 			gss_buffer_t output_token,
136 			const void *type,
137 			const gss_OID mech
138 )
139 {
140     size_t len, outer_len;
141     u_char *p;
142 
143     _gsskrb5_encap_length (in_data->length, &len, &outer_len, mech);
144 
145     output_token->length = outer_len;
146     output_token->value  = malloc (outer_len);
147     if (output_token->value == NULL) {
148 	*minor_status = ENOMEM;
149 	return GSS_S_FAILURE;
150     }
151 
152     p = _gsskrb5_make_header (output_token->value, len, type, mech);
153     memcpy (p, in_data->data, in_data->length);
154     return GSS_S_COMPLETE;
155 }
156