1 /* $NetBSD: kerberos.c,v 1.3 2021/08/14 16:14:52 christos Exp $ */
2
3 /* $OpenLDAP$ */
4 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
5 *
6 * Copyright 1998-2021 The OpenLDAP Foundation.
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted only as authorized by the OpenLDAP
11 * Public License.
12 *
13 * A copy of this license is available in the file LICENSE in the
14 * top-level directory of the distribution or, alternatively, at
15 * <http://www.OpenLDAP.org/license.html>.
16 */
17
18 #include <sys/cdefs.h>
19 __RCSID("$NetBSD: kerberos.c,v 1.3 2021/08/14 16:14:52 christos Exp $");
20
21 #include "portable.h"
22
23 #include <unistd.h>
24
25 #include <lber.h>
26 #include <lber_pvt.h> /* BER_BVC definition */
27 #include "lutil.h"
28 #include <ac/string.h>
29
30 #ifdef HAVE_KRB5
31 #include <krb5.h>
32 #elif defined(HAVE_KRB4)
33 #include <krb.h>
34 #endif
35
36 /* From <ldap_pvt.h> */
37 LDAP_F( char *) ldap_pvt_get_fqdn LDAP_P(( char * ));
38
39 static LUTIL_PASSWD_CHK_FUNC chk_kerberos;
40 static const struct berval scheme = BER_BVC("{KERBEROS}");
41
chk_kerberos(const struct berval * sc,const struct berval * passwd,const struct berval * cred,const char ** text)42 static int chk_kerberos(
43 const struct berval *sc,
44 const struct berval * passwd,
45 const struct berval * cred,
46 const char **text )
47 {
48 unsigned int i;
49 int rtn;
50
51 for( i=0; i<cred->bv_len; i++) {
52 if(cred->bv_val[i] == '\0') {
53 return LUTIL_PASSWD_ERR; /* NUL character in password */
54 }
55 }
56
57 if( cred->bv_val[i] != '\0' ) {
58 return LUTIL_PASSWD_ERR; /* cred must behave like a string */
59 }
60
61 for( i=0; i<passwd->bv_len; i++) {
62 if(passwd->bv_val[i] == '\0') {
63 return LUTIL_PASSWD_ERR; /* NUL character in password */
64 }
65 }
66
67 if( passwd->bv_val[i] != '\0' ) {
68 return LUTIL_PASSWD_ERR; /* passwd must behave like a string */
69 }
70
71 rtn = LUTIL_PASSWD_ERR;
72
73 #ifdef HAVE_KRB5 /* HAVE_HEIMDAL_KRB5 */
74 {
75 /* Portions:
76 * Copyright (c) 1997, 1998, 1999 Kungliga Tekniska H\xf6gskolan
77 * (Royal Institute of Technology, Stockholm, Sweden).
78 * All rights reserved.
79 *
80 * Redistribution and use in source and binary forms, with or without
81 * modification, are permitted provided that the following conditions
82 * are met:
83 *
84 * 1. Redistributions of source code must retain the above copyright
85 * notice, this list of conditions and the following disclaimer.
86 *
87 * 2. Redistributions in binary form must reproduce the above copyright
88 * notice, this list of conditions and the following disclaimer in the
89 * documentation and/or other materials provided with the distribution.
90 *
91 * 3. Neither the name of the Institute nor the names of its contributors
92 * may be used to endorse or promote products derived from this software
93 * without specific prior written permission.
94 *
95 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
96 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
97 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
98 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
99 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
100 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
101 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
102 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
103 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
104 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
105 * SUCH DAMAGE.
106 */
107
108 krb5_context context;
109 krb5_error_code ret;
110 krb5_creds creds;
111 krb5_get_init_creds_opt get_options;
112 krb5_verify_init_creds_opt verify_options;
113 krb5_principal client, server;
114 #ifdef notdef
115 krb5_preauthtype pre_auth_types[] = {KRB5_PADATA_ENC_TIMESTAMP};
116 #endif
117
118 ret = krb5_init_context( &context );
119 if (ret) {
120 return LUTIL_PASSWD_ERR;
121 }
122
123 #ifdef notdef
124 krb5_get_init_creds_opt_set_preauth_list(&get_options,
125 pre_auth_types, 1);
126 #endif
127
128 krb5_get_init_creds_opt_init( &get_options );
129
130 krb5_verify_init_creds_opt_init( &verify_options );
131
132 ret = krb5_parse_name( context, passwd->bv_val, &client );
133
134 if (ret) {
135 krb5_free_context( context );
136 return LUTIL_PASSWD_ERR;
137 }
138
139 ret = krb5_get_init_creds_password( context,
140 &creds, client, cred->bv_val, NULL,
141 NULL, 0, NULL, &get_options );
142
143 if (ret) {
144 krb5_free_principal( context, client );
145 krb5_free_context( context );
146 return LUTIL_PASSWD_ERR;
147 }
148
149 {
150 char *host = ldap_pvt_get_fqdn( NULL );
151
152 if( host == NULL ) {
153 krb5_free_principal( context, client );
154 krb5_free_context( context );
155 return LUTIL_PASSWD_ERR;
156 }
157
158 ret = krb5_sname_to_principal( context,
159 host, "ldap", KRB5_NT_SRV_HST, &server );
160
161 ber_memfree( host );
162 }
163
164 if (ret) {
165 krb5_free_principal( context, client );
166 krb5_free_context( context );
167 return LUTIL_PASSWD_ERR;
168 }
169
170 ret = krb5_verify_init_creds( context,
171 &creds, server, NULL, NULL, &verify_options );
172
173 krb5_free_principal( context, client );
174 krb5_free_principal( context, server );
175 krb5_free_cred_contents( context, &creds );
176 krb5_free_context( context );
177
178 rtn = ret ? LUTIL_PASSWD_ERR : LUTIL_PASSWD_OK;
179 }
180 #elif defined(HAVE_KRB4)
181 {
182 /* Borrowed from Heimdal kpopper */
183 /* Portions:
184 * Copyright (c) 1989 Regents of the University of California.
185 * All rights reserved. The Berkeley software License Agreement
186 * specifies the terms and conditions for redistribution.
187 */
188
189 int status;
190 char lrealm[REALM_SZ];
191 char tkt[MAXHOSTNAMELEN];
192
193 status = krb_get_lrealm(lrealm,1);
194 if (status == KFAILURE) {
195 return LUTIL_PASSWD_ERR;
196 }
197
198 snprintf(tkt, sizeof(tkt), "%s_slapd.%u",
199 TKT_ROOT, (unsigned)getpid());
200 krb_set_tkt_string (tkt);
201
202 status = krb_verify_user( passwd->bv_val, "", lrealm,
203 cred->bv_val, 1, "ldap");
204
205 dest_tkt(); /* no point in keeping the tickets */
206
207 return status == KFAILURE ? LUTIL_PASSWD_ERR : LUTIL_PASSWD_OK;
208 }
209 #endif
210
211 return rtn;
212 }
213
init_module(int argc,char * argv[])214 int init_module(int argc, char *argv[]) {
215 return lutil_passwd_add( (struct berval *)&scheme, chk_kerberos, NULL );
216 }
217