xref: /freebsd/lib/libgssapi/gss_import_name.c (revision b3e7694832e81d7a904a10f525f8797b753bf0d3)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 
29 #include <gssapi/gssapi.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <errno.h>
33 
34 #include "mech_switch.h"
35 #include "utils.h"
36 #include "name.h"
37 
38 static OM_uint32
_gss_import_export_name(OM_uint32 * minor_status,const gss_buffer_t input_name_buffer,gss_name_t * output_name)39 _gss_import_export_name(OM_uint32 *minor_status,
40     const gss_buffer_t input_name_buffer,
41     gss_name_t *output_name)
42 {
43 	OM_uint32 major_status;
44 	unsigned char *p = input_name_buffer->value;
45 	size_t len = input_name_buffer->length;
46 	size_t t;
47 	gss_OID_desc mech_oid;
48 	struct _gss_mech_switch *m;
49 	struct _gss_name *name;
50 	gss_name_t new_canonical_name;
51 
52 	*minor_status = 0;
53 	*output_name = 0;
54 
55 	/*
56 	 * Make sure that TOK_ID is {4, 1}.
57 	 */
58 	if (len < 2)
59 		return (GSS_S_BAD_NAME);
60 	if (p[0] != 4 || p[1] != 1)
61 		return (GSS_S_BAD_NAME);
62 	p += 2;
63 	len -= 2;
64 
65 	/*
66 	 * Get the mech length and the name length and sanity
67 	 * check the size of of the buffer.
68 	 */
69 	if (len < 2)
70 		return (GSS_S_BAD_NAME);
71 	t = (p[0] << 8) + p[1];
72 	p += 2;
73 	len -= 2;
74 
75 	/*
76 	 * Check the DER encoded OID to make sure it agrees with the
77 	 * length we just decoded.
78 	 */
79 	if (p[0] != 6)		/* 6=OID */
80 		return (GSS_S_BAD_NAME);
81 	p++;
82 	len--;
83 	t--;
84 	if (p[0] & 0x80) {
85 		int digits = p[0];
86 		p++;
87 		len--;
88 		t--;
89 		mech_oid.length = 0;
90 		while (digits--) {
91 			mech_oid.length = (mech_oid.length << 8) | p[0];
92 			p++;
93 			len--;
94 			t--;
95 		}
96 	} else {
97 		mech_oid.length = p[0];
98 		p++;
99 		len--;
100 		t--;
101 	}
102 	if (mech_oid.length != t)
103 		return (GSS_S_BAD_NAME);
104 
105 	mech_oid.elements = p;
106 
107 	if (len < t + 4)
108 		return (GSS_S_BAD_NAME);
109 	p += t;
110 	len -= t;
111 
112 	t = (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
113 	p += 4;
114 	len -= 4;
115 
116 	if (len != t)
117 		return (GSS_S_BAD_NAME);
118 
119 	m = _gss_find_mech_switch(&mech_oid);
120 	if (!m)
121 		return (GSS_S_BAD_MECH);
122 
123 	/*
124 	 * Ask the mechanism to import the name.
125 	 */
126 	major_status = m->gm_import_name(minor_status,
127 	    input_name_buffer, GSS_C_NT_EXPORT_NAME, &new_canonical_name);
128 	if (major_status != GSS_S_COMPLETE) {
129 		_gss_mg_error(m, major_status, *minor_status);
130 		return (major_status);
131 	}
132 
133 	/*
134 	 * Now we make a new name and mark it as an MN.
135 	 */
136 	name = _gss_make_name(m, new_canonical_name);
137 	if (!name) {
138 		m->gm_release_name(minor_status, &new_canonical_name);
139 		return (GSS_S_FAILURE);
140 	}
141 
142 	*output_name = (gss_name_t) name;
143 
144 	*minor_status = 0;
145 	return (GSS_S_COMPLETE);
146 }
147 
148 OM_uint32
gss_import_name(OM_uint32 * minor_status,const gss_buffer_t input_name_buffer,const gss_OID input_name_type,gss_name_t * output_name)149 gss_import_name(OM_uint32 *minor_status,
150     const gss_buffer_t input_name_buffer,
151     const gss_OID input_name_type,
152     gss_name_t *output_name)
153 {
154 	gss_OID			name_type = input_name_type;
155 	OM_uint32		major_status;
156 	struct _gss_name	*name;
157 
158 	*output_name = GSS_C_NO_NAME;
159 
160 	if (input_name_buffer->length == 0) {
161 		*minor_status = 0;
162 		return (GSS_S_BAD_NAME);
163 	}
164 
165 	/*
166 	 * Use GSS_NT_USER_NAME as default name type.
167 	 */
168 	if (name_type == GSS_C_NO_OID)
169 		name_type = GSS_C_NT_USER_NAME;
170 
171 	/*
172 	 * If this is an exported name, we need to parse it to find
173 	 * the mechanism and then import it as an MN. See RFC 2743
174 	 * section 3.2 for a description of the format.
175 	 */
176 	if (gss_oid_equal(name_type, GSS_C_NT_EXPORT_NAME)) {
177 		return _gss_import_export_name(minor_status,
178 		    input_name_buffer, output_name);
179 	}
180 
181 	/*
182 	 * Only allow certain name types. This is pretty bogus - we
183 	 * should figure out the list of supported name types using
184 	 * gss_inquire_names_for_mech.
185 	 */
186 	if (!gss_oid_equal(name_type, GSS_C_NT_USER_NAME)
187 	    && !gss_oid_equal(name_type, GSS_C_NT_MACHINE_UID_NAME)
188 	    && !gss_oid_equal(name_type, GSS_C_NT_STRING_UID_NAME)
189 	    && !gss_oid_equal(name_type, GSS_C_NT_HOSTBASED_SERVICE_X)
190 	    && !gss_oid_equal(name_type, GSS_C_NT_HOSTBASED_SERVICE)
191 	    && !gss_oid_equal(name_type, GSS_C_NT_ANONYMOUS)
192 	    && !gss_oid_equal(name_type, GSS_KRB5_NT_PRINCIPAL_NAME)) {
193 		*minor_status = 0;
194 		return (GSS_S_BAD_NAMETYPE);
195 	}
196 
197 	*minor_status = 0;
198 	name = malloc(sizeof(struct _gss_name));
199 	if (!name) {
200 		*minor_status = ENOMEM;
201 		return (GSS_S_FAILURE);
202 	}
203 	memset(name, 0, sizeof(struct _gss_name));
204 
205 	major_status = _gss_copy_oid(minor_status,
206 	    name_type, &name->gn_type);
207 	if (major_status) {
208 		free(name);
209 		return (GSS_S_FAILURE);
210 	}
211 
212 	major_status = _gss_copy_buffer(minor_status,
213 	    input_name_buffer, &name->gn_value);
214 	if (major_status) {
215 		gss_name_t rname = (gss_name_t)name;
216 		gss_release_name(minor_status, &rname);
217 		return (GSS_S_FAILURE);
218 	}
219 
220 	SLIST_INIT(&name->gn_mn);
221 
222 	*output_name = (gss_name_t) name;
223 	return (GSS_S_COMPLETE);
224 }
225