1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2008 Doug Rabson
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD$
29 */
30
31 #include <gssapi/gssapi.h>
32 #include <stdlib.h>
33 #include <string.h>
34
35 #include "utils.h"
36
37 OM_uint32
gss_encapsulate_token(const gss_buffer_t input_token,gss_OID oid,gss_buffer_t output_token)38 gss_encapsulate_token(const gss_buffer_t input_token, gss_OID oid,
39 gss_buffer_t output_token)
40 {
41 unsigned char *p;
42 size_t len, inside_len;
43 size_t a, b;
44 int i;
45
46 _gss_buffer_zero(output_token);
47
48 /*
49 * First time around, we calculate the size, second time, we
50 * encode the token.
51 */
52 p = NULL;
53 for (i = 0; i < 2; i++) {
54 len = 0;
55
56 /*
57 * Token starts with [APPLICATION 0] SEQUENCE.
58 */
59 if (p)
60 *p++ = 0x60;
61 len++;
62
63 /*
64 * The length embedded in the token is the space
65 * needed for the encapsulated oid plus the length of
66 * the inner token.
67 */
68 if (oid->length > 127)
69 return (GSS_S_DEFECTIVE_TOKEN);
70
71 inside_len = 2 + oid->length + input_token->length;
72
73 /*
74 * Figure out how to encode the length
75 */
76 if (inside_len < 128) {
77 if (p)
78 *p++ = inside_len;
79 len++;
80 } else {
81 b = 1;
82 if (inside_len >= 0x100)
83 b++;
84 if (inside_len >= 0x10000)
85 b++;
86 if (inside_len >= 0x1000000)
87 b++;
88 if (p)
89 *p++ = b | 0x80;
90 len++;
91 a = inside_len << 8*(4 - b);
92 while (b) {
93 if (p)
94 *p++ = (a >> 24);
95 a <<= 8;
96 len++;
97 b--;
98 }
99 }
100
101 /*
102 * Encode the OID for the mechanism. Simplify life by
103 * assuming that the OID length is less than 128 bytes.
104 */
105 if (p)
106 *p++ = 0x06;
107 len++;
108 if (p)
109 *p++ = oid->length;
110 len++;
111 if (p) {
112 memcpy(p, oid->elements, oid->length);
113 p += oid->length;
114 }
115 len += oid->length;
116
117 if (p) {
118 memcpy(p, input_token->value, input_token->length);
119 p += input_token->length;
120 }
121 len += input_token->length;
122
123 if (i == 0) {
124 output_token->length = len;
125 output_token->value = malloc(len);
126 if (!output_token->value)
127 return (GSS_S_DEFECTIVE_TOKEN);
128 p = output_token->value;
129 }
130 }
131
132 return (GSS_S_COMPLETE);
133 }
134