xref: /freebsd/crypto/heimdal/lib/gssapi/krb5/encapsulate.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*
2  * Copyright (c) 1997 - 2003 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 "gsskrb5_locl.h"
35 
36 void
37 _gssapi_encap_length (size_t data_len,
38 		      size_t *len,
39 		      size_t *total_len,
40 		      const gss_OID mech)
41 {
42     size_t len_len;
43 
44     *len = 1 + 1 + mech->length + data_len;
45 
46     len_len = der_length_len(*len);
47 
48     *total_len = 1 + len_len + *len;
49 }
50 
51 void
52 _gsskrb5_encap_length (size_t data_len,
53 			  size_t *len,
54 			  size_t *total_len,
55 			  const gss_OID mech)
56 {
57     _gssapi_encap_length(data_len + 2, len, total_len, mech);
58 }
59 
60 void *
61 _gsskrb5_make_header (void *ptr,
62 			 size_t len,
63 			 const void *type,
64 			 const gss_OID mech)
65 {
66     u_char *p = ptr;
67     p = _gssapi_make_mech_header(p, len, mech);
68     memcpy (p, type, 2);
69     p += 2;
70     return p;
71 }
72 
73 void *
74 _gssapi_make_mech_header(void *ptr,
75 			 size_t len,
76 			 const gss_OID mech)
77 {
78     u_char *p = ptr;
79     int e;
80     size_t len_len, foo;
81 
82     *p++ = 0x60;
83     len_len = der_length_len(len);
84     e = der_put_length (p + len_len - 1, len_len, len, &foo);
85     if(e || foo != len_len)
86 	abort ();
87     p += len_len;
88     *p++ = 0x06;
89     *p++ = mech->length;
90     memcpy (p, mech->elements, mech->length);
91     p += mech->length;
92     return p;
93 }
94 
95 /*
96  * Give it a krb5_data and it will encapsulate with extra GSS-API wrappings.
97  */
98 
99 OM_uint32
100 _gssapi_encapsulate(
101     OM_uint32 *minor_status,
102     const krb5_data *in_data,
103     gss_buffer_t output_token,
104     const gss_OID mech
105 )
106 {
107     size_t len, outer_len;
108     void *p;
109 
110     _gssapi_encap_length (in_data->length, &len, &outer_len, mech);
111 
112     output_token->length = outer_len;
113     output_token->value  = malloc (outer_len);
114     if (output_token->value == NULL) {
115 	*minor_status = ENOMEM;
116 	return GSS_S_FAILURE;
117     }
118 
119     p = _gssapi_make_mech_header (output_token->value, len, mech);
120     memcpy (p, in_data->data, in_data->length);
121     return GSS_S_COMPLETE;
122 }
123 
124 /*
125  * Give it a krb5_data and it will encapsulate with extra GSS-API krb5
126  * wrappings.
127  */
128 
129 OM_uint32
130 _gsskrb5_encapsulate(
131 			OM_uint32 *minor_status,
132 			const krb5_data *in_data,
133 			gss_buffer_t output_token,
134 			const void *type,
135 			const gss_OID mech
136 )
137 {
138     size_t len, outer_len;
139     u_char *p;
140 
141     _gsskrb5_encap_length (in_data->length, &len, &outer_len, mech);
142 
143     output_token->length = outer_len;
144     output_token->value  = malloc (outer_len);
145     if (output_token->value == NULL) {
146 	*minor_status = ENOMEM;
147 	return GSS_S_FAILURE;
148     }
149 
150     p = _gsskrb5_make_header (output_token->value, len, type, mech);
151     memcpy (p, in_data->data, in_data->length);
152     return GSS_S_COMPLETE;
153 }
154