xref: /freebsd/lib/libgssapi/gss_import_name.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2005 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 #include <errno.h>
35 
36 #include "mech_switch.h"
37 #include "utils.h"
38 #include "name.h"
39 
40 static OM_uint32
41 _gss_import_export_name(OM_uint32 *minor_status,
42     const gss_buffer_t input_name_buffer,
43     gss_name_t *output_name)
44 {
45 	OM_uint32 major_status;
46 	unsigned char *p = input_name_buffer->value;
47 	size_t len = input_name_buffer->length;
48 	size_t t;
49 	gss_OID_desc mech_oid;
50 	struct _gss_mech_switch *m;
51 	struct _gss_name *name;
52 	gss_name_t new_canonical_name;
53 
54 	*minor_status = 0;
55 	*output_name = 0;
56 
57 	/*
58 	 * Make sure that TOK_ID is {4, 1}.
59 	 */
60 	if (len < 2)
61 		return (GSS_S_BAD_NAME);
62 	if (p[0] != 4 || p[1] != 1)
63 		return (GSS_S_BAD_NAME);
64 	p += 2;
65 	len -= 2;
66 
67 	/*
68 	 * Get the mech length and the name length and sanity
69 	 * check the size of of the buffer.
70 	 */
71 	if (len < 2)
72 		return (GSS_S_BAD_NAME);
73 	t = (p[0] << 8) + p[1];
74 	p += 2;
75 	len -= 2;
76 
77 	/*
78 	 * Check the DER encoded OID to make sure it agrees with the
79 	 * length we just decoded.
80 	 */
81 	if (p[0] != 6)		/* 6=OID */
82 		return (GSS_S_BAD_NAME);
83 	p++;
84 	len--;
85 	t--;
86 	if (p[0] & 0x80) {
87 		int digits = p[0];
88 		p++;
89 		len--;
90 		t--;
91 		mech_oid.length = 0;
92 		while (digits--) {
93 			mech_oid.length = (mech_oid.length << 8) | p[0];
94 			p++;
95 			len--;
96 			t--;
97 		}
98 	} else {
99 		mech_oid.length = p[0];
100 		p++;
101 		len--;
102 		t--;
103 	}
104 	if (mech_oid.length != t)
105 		return (GSS_S_BAD_NAME);
106 
107 	mech_oid.elements = p;
108 
109 	if (len < t + 4)
110 		return (GSS_S_BAD_NAME);
111 	p += t;
112 	len -= t;
113 
114 	t = (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
115 	p += 4;
116 	len -= 4;
117 
118 	if (len != t)
119 		return (GSS_S_BAD_NAME);
120 
121 	m = _gss_find_mech_switch(&mech_oid);
122 	if (!m)
123 		return (GSS_S_BAD_MECH);
124 
125 	/*
126 	 * Ask the mechanism to import the name.
127 	 */
128 	major_status = m->gm_import_name(minor_status,
129 	    input_name_buffer, GSS_C_NT_EXPORT_NAME, &new_canonical_name);
130 	if (major_status != GSS_S_COMPLETE) {
131 		_gss_mg_error(m, major_status, *minor_status);
132 		return (major_status);
133 	}
134 
135 	/*
136 	 * Now we make a new name and mark it as an MN.
137 	 */
138 	name = _gss_make_name(m, new_canonical_name);
139 	if (!name) {
140 		m->gm_release_name(minor_status, &new_canonical_name);
141 		return (GSS_S_FAILURE);
142 	}
143 
144 	*output_name = (gss_name_t) name;
145 
146 	*minor_status = 0;
147 	return (GSS_S_COMPLETE);
148 }
149 
150 OM_uint32
151 gss_import_name(OM_uint32 *minor_status,
152     const gss_buffer_t input_name_buffer,
153     const gss_OID input_name_type,
154     gss_name_t *output_name)
155 {
156 	gss_OID			name_type = input_name_type;
157 	OM_uint32		major_status;
158 	struct _gss_name	*name;
159 
160 	*output_name = GSS_C_NO_NAME;
161 
162 	if (input_name_buffer->length == 0) {
163 		*minor_status = 0;
164 		return (GSS_S_BAD_NAME);
165 	}
166 
167 	/*
168 	 * Use GSS_NT_USER_NAME as default name type.
169 	 */
170 	if (name_type == GSS_C_NO_OID)
171 		name_type = GSS_C_NT_USER_NAME;
172 
173 	/*
174 	 * If this is an exported name, we need to parse it to find
175 	 * the mechanism and then import it as an MN. See RFC 2743
176 	 * section 3.2 for a description of the format.
177 	 */
178 	if (gss_oid_equal(name_type, GSS_C_NT_EXPORT_NAME)) {
179 		return _gss_import_export_name(minor_status,
180 		    input_name_buffer, output_name);
181 	}
182 
183 	/*
184 	 * Only allow certain name types. This is pretty bogus - we
185 	 * should figure out the list of supported name types using
186 	 * gss_inquire_names_for_mech.
187 	 */
188 	if (!gss_oid_equal(name_type, GSS_C_NT_USER_NAME)
189 	    && !gss_oid_equal(name_type, GSS_C_NT_MACHINE_UID_NAME)
190 	    && !gss_oid_equal(name_type, GSS_C_NT_STRING_UID_NAME)
191 	    && !gss_oid_equal(name_type, GSS_C_NT_HOSTBASED_SERVICE_X)
192 	    && !gss_oid_equal(name_type, GSS_C_NT_HOSTBASED_SERVICE)
193 	    && !gss_oid_equal(name_type, GSS_C_NT_ANONYMOUS)
194 	    && !gss_oid_equal(name_type, GSS_KRB5_NT_PRINCIPAL_NAME)) {
195 		*minor_status = 0;
196 		return (GSS_S_BAD_NAMETYPE);
197 	}
198 
199 	*minor_status = 0;
200 	name = malloc(sizeof(struct _gss_name));
201 	if (!name) {
202 		*minor_status = ENOMEM;
203 		return (GSS_S_FAILURE);
204 	}
205 	memset(name, 0, sizeof(struct _gss_name));
206 
207 	major_status = _gss_copy_oid(minor_status,
208 	    name_type, &name->gn_type);
209 	if (major_status) {
210 		free(name);
211 		return (GSS_S_FAILURE);
212 	}
213 
214 	major_status = _gss_copy_buffer(minor_status,
215 	    input_name_buffer, &name->gn_value);
216 	if (major_status) {
217 		gss_name_t rname = (gss_name_t)name;
218 		gss_release_name(minor_status, &rname);
219 		return (GSS_S_FAILURE);
220 	}
221 
222 	SLIST_INIT(&name->gn_mn);
223 
224 	*output_name = (gss_name_t) name;
225 	return (GSS_S_COMPLETE);
226 }
227