1 /*-
2 * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
3 * Copyright (c) 2004-2017 Dag-Erling Smørgrav
4 * All rights reserved.
5 *
6 * This software was developed for the FreeBSD Project by ThinkSec AS and
7 * Network Associates Laboratories, the Security Research Division of
8 * Network Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035
9 * ("CBOSS"), as part of the DARPA CHATS research program.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. The name of the author may not be used to endorse or promote
20 * products derived from this software without specific prior written
21 * permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 #ifdef HAVE_CONFIG_H
37 # include "config.h"
38 #endif
39
40 #include <sys/param.h>
41
42 #include <stdint.h>
43
44 #include <security/pam_appl.h>
45
46 #include "openpam_impl.h"
47
48 #if !defined(OPENPAM_RELAX_CHECKS)
49 static void openpam_check_error_code(int, int);
50 #else
51 #define openpam_check_error_code(a, b)
52 #endif /* !defined(OPENPAM_RELAX_CHECKS) */
53
54 /*
55 * OpenPAM internal
56 *
57 * Execute a module chain
58 */
59
60 int
openpam_dispatch(pam_handle_t * pamh,int primitive,int flags)61 openpam_dispatch(pam_handle_t *pamh,
62 int primitive,
63 int flags)
64 {
65 pam_chain_t *chain;
66 int err, fail, nsuccess, r;
67 int debug;
68
69 ENTER();
70
71 /* prevent recursion */
72 if (pamh->current != NULL) {
73 openpam_log(PAM_LOG_ERROR,
74 "%s() called while %s::%s() is in progress",
75 pam_func_name[primitive],
76 pamh->current->module->path,
77 pam_sm_func_name[pamh->primitive]);
78 RETURNC(PAM_ABORT);
79 }
80
81 /* pick a chain */
82 switch (primitive) {
83 case PAM_SM_AUTHENTICATE:
84 case PAM_SM_SETCRED:
85 chain = pamh->chains[PAM_AUTH];
86 break;
87 case PAM_SM_ACCT_MGMT:
88 chain = pamh->chains[PAM_ACCOUNT];
89 break;
90 case PAM_SM_OPEN_SESSION:
91 case PAM_SM_CLOSE_SESSION:
92 chain = pamh->chains[PAM_SESSION];
93 break;
94 case PAM_SM_CHAUTHTOK:
95 chain = pamh->chains[PAM_PASSWORD];
96 break;
97 default:
98 RETURNC(PAM_SYSTEM_ERR);
99 }
100
101 /* execute */
102 err = PAM_SUCCESS;
103 fail = nsuccess = 0;
104 for (; chain != NULL; chain = chain->next) {
105 if (chain->module->func[primitive] == NULL) {
106 openpam_log(PAM_LOG_ERROR, "%s: no %s()",
107 chain->module->path, pam_sm_func_name[primitive]);
108 r = PAM_SYMBOL_ERR;
109 } else {
110 pamh->primitive = primitive;
111 pamh->current = chain;
112 debug = (openpam_get_option(pamh, "debug") != NULL);
113 if (debug)
114 ++openpam_debug;
115 openpam_log(PAM_LOG_LIBDEBUG, "calling %s() in %s",
116 pam_sm_func_name[primitive], chain->module->path);
117 r = (chain->module->func[primitive])(pamh, flags,
118 chain->optc, (const char **)(intptr_t)chain->optv);
119 pamh->current = NULL;
120 openpam_log(PAM_LOG_LIBDEBUG, "%s: %s(): %s",
121 chain->module->path, pam_sm_func_name[primitive],
122 pam_strerror(pamh, r));
123 if (debug)
124 --openpam_debug;
125 }
126
127 if (r == PAM_IGNORE)
128 continue;
129 if (r == PAM_SUCCESS) {
130 ++nsuccess;
131 /*
132 * For pam_setcred() and pam_chauthtok() with the
133 * PAM_PRELIM_CHECK flag, treat "sufficient" as
134 * "optional".
135 */
136 if ((chain->flag == PAM_SUFFICIENT ||
137 chain->flag == PAM_BINDING) && !fail &&
138 primitive != PAM_SM_SETCRED &&
139 !(primitive == PAM_SM_CHAUTHTOK &&
140 (flags & PAM_PRELIM_CHECK)))
141 break;
142 continue;
143 }
144
145 openpam_check_error_code(primitive, r);
146
147 /*
148 * Record the return code from the first module to
149 * fail. If a required module fails, record the
150 * return code from the first required module to fail.
151 */
152 if (err == PAM_SUCCESS)
153 err = r;
154 if ((chain->flag == PAM_REQUIRED ||
155 chain->flag == PAM_BINDING) && !fail) {
156 openpam_log(PAM_LOG_LIBDEBUG, "required module failed");
157 fail = 1;
158 err = r;
159 }
160
161 /*
162 * If a requisite module fails, terminate the chain
163 * immediately.
164 */
165 if (chain->flag == PAM_REQUISITE) {
166 openpam_log(PAM_LOG_LIBDEBUG, "requisite module failed");
167 fail = 1;
168 break;
169 }
170 }
171
172 if (!fail && err != PAM_NEW_AUTHTOK_REQD)
173 err = PAM_SUCCESS;
174
175 /*
176 * Require the chain to be non-empty, and at least one module
177 * in the chain to be successful, so that we don't fail open.
178 */
179 if (err == PAM_SUCCESS && nsuccess < 1) {
180 openpam_log(PAM_LOG_ERROR,
181 "all modules were unsuccessful for %s()",
182 pam_sm_func_name[primitive]);
183 err = PAM_SYSTEM_ERR;
184 }
185
186 RETURNC(err);
187 }
188
189 #if !defined(OPENPAM_RELAX_CHECKS)
190 static void
openpam_check_error_code(int primitive,int r)191 openpam_check_error_code(int primitive, int r)
192 {
193 /* common error codes */
194 if (r == PAM_SUCCESS ||
195 r == PAM_SYSTEM_ERR ||
196 r == PAM_SERVICE_ERR ||
197 r == PAM_BUF_ERR ||
198 r == PAM_CONV_ERR ||
199 r == PAM_PERM_DENIED ||
200 r == PAM_ABORT)
201 return;
202
203 /* specific error codes */
204 switch (primitive) {
205 case PAM_SM_AUTHENTICATE:
206 if (r == PAM_AUTH_ERR ||
207 r == PAM_CRED_INSUFFICIENT ||
208 r == PAM_AUTHINFO_UNAVAIL ||
209 r == PAM_USER_UNKNOWN ||
210 r == PAM_MAXTRIES)
211 return;
212 break;
213 case PAM_SM_SETCRED:
214 if (r == PAM_CRED_UNAVAIL ||
215 r == PAM_CRED_EXPIRED ||
216 r == PAM_USER_UNKNOWN ||
217 r == PAM_CRED_ERR)
218 return;
219 break;
220 case PAM_SM_ACCT_MGMT:
221 if (r == PAM_USER_UNKNOWN ||
222 r == PAM_AUTH_ERR ||
223 r == PAM_NEW_AUTHTOK_REQD ||
224 r == PAM_ACCT_EXPIRED)
225 return;
226 break;
227 case PAM_SM_OPEN_SESSION:
228 case PAM_SM_CLOSE_SESSION:
229 if (r == PAM_SESSION_ERR)
230 return;
231 break;
232 case PAM_SM_CHAUTHTOK:
233 if (r == PAM_PERM_DENIED ||
234 r == PAM_AUTHTOK_ERR ||
235 r == PAM_AUTHTOK_RECOVERY_ERR ||
236 r == PAM_AUTHTOK_LOCK_BUSY ||
237 r == PAM_AUTHTOK_DISABLE_AGING ||
238 r == PAM_TRY_AGAIN)
239 return;
240 break;
241 }
242
243 openpam_log(PAM_LOG_ERROR, "%s(): unexpected return value %d",
244 pam_sm_func_name[primitive], r);
245 }
246 #endif /* !defined(OPENPAM_RELAX_CHECKS) */
247
248 /*
249 * NODOC
250 *
251 * Error codes:
252 */
253