1/*
2 * Copyright (c) 2011, PADL Software Pty Ltd.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 *
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 * 3. Neither the name of PADL Software nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY PADL SOFTWARE AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL PADL SOFTWARE OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#include "mech_locl.h"
34
35gss_buffer_desc GSSAPI_LIB_VARIABLE __gss_c_attr_local_login_user =  {
36    sizeof("local-login-user") - 1,
37    "local-login-user"
38};
39
40static OM_uint32
41mech_authorize_localname(OM_uint32 *minor_status,
42	                 const struct _gss_name *name,
43	                 const struct _gss_name *user)
44{
45    OM_uint32 major_status = GSS_S_NAME_NOT_MN;
46    struct _gss_mechanism_name *mn;
47
48    HEIM_SLIST_FOREACH(mn, &name->gn_mn, gmn_link) {
49        gssapi_mech_interface m = mn->gmn_mech;
50
51        if (m->gm_authorize_localname == NULL) {
52            major_status = GSS_S_UNAVAILABLE;
53            continue;
54        }
55
56        major_status = m->gm_authorize_localname(minor_status,
57                                                 mn->gmn_name,
58                                                 &user->gn_value,
59                                                 &user->gn_type);
60        if (major_status != GSS_S_UNAUTHORIZED)
61            break;
62    }
63
64    return major_status;
65}
66
67/*
68 * Naming extensions based local login authorization.
69 */
70static OM_uint32
71attr_authorize_localname(OM_uint32 *minor_status,
72	                 const struct _gss_name *name,
73	                 const struct _gss_name *user)
74{
75    OM_uint32 major_status = GSS_S_UNAVAILABLE;
76    int more = -1;
77
78    if (!gss_oid_equal(&user->gn_type, GSS_C_NT_USER_NAME))
79        return GSS_S_BAD_NAMETYPE;
80
81    while (more != 0 && major_status != GSS_S_COMPLETE) {
82	OM_uint32 tmpMajor, tmpMinor;
83	gss_buffer_desc value;
84	gss_buffer_desc display_value;
85	int authenticated = 0, complete = 0;
86
87	tmpMajor = gss_get_name_attribute(minor_status,
88					  (gss_name_t)name,
89					  GSS_C_ATTR_LOCAL_LOGIN_USER,
90					  &authenticated,
91					  &complete,
92					  &value,
93					  &display_value,
94					  &more);
95	if (GSS_ERROR(tmpMajor)) {
96	    major_status = tmpMajor;
97	    break;
98	}
99
100	/* If attribute is present, return an authoritative error code. */
101	if (authenticated &&
102	    value.length == user->gn_value.length &&
103	    memcmp(value.value, user->gn_value.value, user->gn_value.length) == 0)
104	    major_status = GSS_S_COMPLETE;
105	else
106	    major_status = GSS_S_UNAUTHORIZED;
107
108	gss_release_buffer(&tmpMinor, &value);
109	gss_release_buffer(&tmpMinor, &display_value);
110    }
111
112    return major_status;
113}
114
115GSSAPI_LIB_FUNCTION OM_uint32 GSSAPI_LIB_CALL
116gss_authorize_localname(OM_uint32 *minor_status,
117	                const gss_name_t gss_name,
118	                const gss_name_t gss_user)
119
120{
121    OM_uint32 major_status;
122    const struct _gss_name *name = (const struct _gss_name *) gss_name;
123    const struct _gss_name *user = (const struct _gss_name *) gss_user;
124    int mechAvailable = 0;
125
126    *minor_status = 0;
127
128    if (gss_name == GSS_C_NO_NAME || gss_user == GSS_C_NO_NAME)
129        return GSS_S_CALL_INACCESSIBLE_READ;
130
131    /*
132     * We should check that the user name is not a mechanism name, but
133     * as Heimdal always calls the mechanism's gss_import_name(), it's
134     * not possible to make this check.
135     */
136#if 0
137    if (HEIM_SLIST_FIRST(&user->gn_mn) != NULL)
138        return GSS_S_BAD_NAME;
139#endif
140
141    /* If mech returns yes, we return yes */
142    major_status = mech_authorize_localname(minor_status, name, user);
143    if (major_status == GSS_S_COMPLETE)
144	return GSS_S_COMPLETE;
145    else if (major_status != GSS_S_UNAVAILABLE)
146	mechAvailable = 1;
147
148    /* If attribute exists, it is authoritative */
149    major_status = attr_authorize_localname(minor_status, name, user);
150    if (major_status == GSS_S_COMPLETE || major_status == GSS_S_UNAUTHORIZED)
151	return major_status;
152
153    /* If mechanism did not implement SPI, compare the local name */
154    if (mechAvailable == 0) {
155	int match = 0;
156
157        major_status = gss_compare_name(minor_status, gss_name,
158                                        gss_user, &match);
159	if (major_status == GSS_S_COMPLETE && match == 0)
160	    major_status = GSS_S_UNAUTHORIZED;
161    }
162
163    return major_status;
164}
165
166GSSAPI_LIB_FUNCTION int GSSAPI_LIB_CALL
167gss_userok(const gss_name_t name,
168           const char *user)
169{
170    OM_uint32 major_status, minor_status;
171    gss_buffer_desc userBuf;
172    gss_name_t userName;
173
174    userBuf.value = (void *)user;
175    userBuf.length = strlen(user);
176
177    major_status = gss_import_name(&minor_status, &userBuf,
178                                   GSS_C_NT_USER_NAME, &userName);
179    if (GSS_ERROR(major_status))
180        return 0;
181
182    major_status = gss_authorize_localname(&minor_status, name, userName);
183
184    gss_release_name(&minor_status, &userName);
185
186    return (major_status == GSS_S_COMPLETE);
187}
188