1 /* $NetBSD: verify_init.c,v 1.2 2017/01/28 21:31:49 christos Exp $ */
2
3 /*
4 * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
5 * (Royal Institute of Technology, Stockholm, Sweden).
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * 3. Neither the name of the Institute nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #include "krb5_locl.h"
37
38 KRB5_LIB_FUNCTION void KRB5_LIB_CALL
krb5_verify_init_creds_opt_init(krb5_verify_init_creds_opt * options)39 krb5_verify_init_creds_opt_init(krb5_verify_init_creds_opt *options)
40 {
41 memset (options, 0, sizeof(*options));
42 }
43
44 KRB5_LIB_FUNCTION void KRB5_LIB_CALL
krb5_verify_init_creds_opt_set_ap_req_nofail(krb5_verify_init_creds_opt * options,int ap_req_nofail)45 krb5_verify_init_creds_opt_set_ap_req_nofail(krb5_verify_init_creds_opt *options,
46 int ap_req_nofail)
47 {
48 options->flags |= KRB5_VERIFY_INIT_CREDS_OPT_AP_REQ_NOFAIL;
49 options->ap_req_nofail = ap_req_nofail;
50 }
51
52 /*
53 *
54 */
55
56 static krb5_boolean
fail_verify_is_ok(krb5_context context,krb5_verify_init_creds_opt * options)57 fail_verify_is_ok (krb5_context context,
58 krb5_verify_init_creds_opt *options)
59 {
60
61 if (options && (options->flags & KRB5_VERIFY_INIT_CREDS_OPT_AP_REQ_NOFAIL)
62 && options->ap_req_nofail != 0)
63 return FALSE;
64
65 if (krb5_config_get_bool(context,
66 NULL,
67 "libdefaults",
68 "verify_ap_req_nofail",
69 NULL))
70 return FALSE;
71
72 return TRUE;
73 }
74
75 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_verify_init_creds(krb5_context context,krb5_creds * creds,krb5_principal ap_req_server,krb5_keytab ap_req_keytab,krb5_ccache * ccache,krb5_verify_init_creds_opt * options)76 krb5_verify_init_creds(krb5_context context,
77 krb5_creds *creds,
78 krb5_principal ap_req_server,
79 krb5_keytab ap_req_keytab,
80 krb5_ccache *ccache,
81 krb5_verify_init_creds_opt *options)
82 {
83 krb5_error_code ret;
84 krb5_data req;
85 krb5_ccache local_ccache = NULL;
86 krb5_creds *new_creds = NULL;
87 krb5_auth_context auth_context = NULL;
88 krb5_principal server = NULL;
89 krb5_keytab keytab = NULL;
90
91 krb5_data_zero (&req);
92
93 if (ap_req_server == NULL) {
94 char local_hostname[MAXHOSTNAMELEN];
95
96 if (gethostname (local_hostname, sizeof(local_hostname)) < 0) {
97 ret = errno;
98 krb5_set_error_message (context, ret, "gethostname: %s",
99 strerror(ret));
100 return ret;
101 }
102
103 ret = krb5_sname_to_principal (context,
104 local_hostname,
105 "host",
106 KRB5_NT_SRV_HST,
107 &server);
108 if (ret)
109 goto cleanup;
110 } else
111 server = ap_req_server;
112
113 if (ap_req_keytab == NULL) {
114 ret = krb5_kt_default (context, &keytab);
115 if (ret)
116 goto cleanup;
117 } else
118 keytab = ap_req_keytab;
119
120 if (ccache && *ccache)
121 local_ccache = *ccache;
122 else {
123 ret = krb5_cc_new_unique(context, krb5_cc_type_memory,
124 NULL, &local_ccache);
125 if (ret)
126 goto cleanup;
127 ret = krb5_cc_initialize (context,
128 local_ccache,
129 creds->client);
130 if (ret)
131 goto cleanup;
132 ret = krb5_cc_store_cred (context,
133 local_ccache,
134 creds);
135 if (ret)
136 goto cleanup;
137 }
138
139 if (!krb5_principal_compare (context, server, creds->server)) {
140 krb5_creds match_cred;
141
142 memset (&match_cred, 0, sizeof(match_cred));
143
144 match_cred.client = creds->client;
145 match_cred.server = server;
146
147 ret = krb5_get_credentials (context,
148 0,
149 local_ccache,
150 &match_cred,
151 &new_creds);
152 if (ret) {
153 if (fail_verify_is_ok (context, options))
154 ret = 0;
155 goto cleanup;
156 }
157 creds = new_creds;
158 }
159
160 ret = krb5_mk_req_extended (context,
161 &auth_context,
162 0,
163 NULL,
164 creds,
165 &req);
166
167 krb5_auth_con_free (context, auth_context);
168 auth_context = NULL;
169
170 if (ret)
171 goto cleanup;
172
173 ret = krb5_rd_req (context,
174 &auth_context,
175 &req,
176 server,
177 keytab,
178 0,
179 NULL);
180
181 if (ret == KRB5_KT_NOTFOUND && fail_verify_is_ok (context, options))
182 ret = 0;
183 cleanup:
184 if (auth_context)
185 krb5_auth_con_free (context, auth_context);
186 krb5_data_free (&req);
187 if (new_creds != NULL)
188 krb5_free_creds (context, new_creds);
189 if (ap_req_server == NULL && server)
190 krb5_free_principal (context, server);
191 if (ap_req_keytab == NULL && keytab)
192 krb5_kt_close (context, keytab);
193 if (local_ccache != NULL
194 &&
195 (ccache == NULL
196 || (ret != 0 && *ccache == NULL)))
197 krb5_cc_destroy (context, local_ccache);
198
199 if (ret == 0 && ccache != NULL && *ccache == NULL)
200 *ccache = local_ccache;
201
202 return ret;
203 }
204
205 /**
206 * Validate the newly fetch credential, see also krb5_verify_init_creds().
207 *
208 * @param context a Kerberos 5 context
209 * @param creds the credentials to verify
210 * @param client the client name to match up
211 * @param ccache the credential cache to use
212 * @param service a service name to use, used with
213 * krb5_sname_to_principal() to build a hostname to use to
214 * verify.
215 *
216 * @ingroup krb5_ccache
217 */
218
219 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_get_validated_creds(krb5_context context,krb5_creds * creds,krb5_principal client,krb5_ccache ccache,char * service)220 krb5_get_validated_creds(krb5_context context,
221 krb5_creds *creds,
222 krb5_principal client,
223 krb5_ccache ccache,
224 char *service)
225 {
226 krb5_verify_init_creds_opt vopt;
227 krb5_principal server;
228 krb5_error_code ret;
229
230 if (krb5_principal_compare(context, creds->client, client) != TRUE) {
231 krb5_set_error_message(context, KRB5_PRINC_NOMATCH,
232 N_("Validation credentials and client "
233 "doesn't match", ""));
234 return KRB5_PRINC_NOMATCH;
235 }
236
237 ret = krb5_sname_to_principal (context, NULL, service,
238 KRB5_NT_SRV_HST, &server);
239 if(ret)
240 return ret;
241
242 krb5_verify_init_creds_opt_init(&vopt);
243
244 ret = krb5_verify_init_creds(context, creds, server, NULL, NULL, &vopt);
245 krb5_free_principal(context, server);
246
247 return ret;
248 }
249