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 * $OpenPAM: openpam_dispatch.c 938 2017-04-30 21:34:42Z des $
36 */
37
38 #ifdef HAVE_CONFIG_H
39 # include "config.h"
40 #endif
41
42 #include <sys/param.h>
43
44 #include <stdint.h>
45
46 #include <security/pam_appl.h>
47
48 #include "openpam_impl.h"
49
50 #if !defined(OPENPAM_RELAX_CHECKS)
51 static void openpam_check_error_code(int, int);
52 #else
53 #define openpam_check_error_code(a, b)
54 #endif /* !defined(OPENPAM_RELAX_CHECKS) */
55
56 /*
57 * OpenPAM internal
58 *
59 * Execute a module chain
60 */
61
62 int
openpam_dispatch(pam_handle_t * pamh,int primitive,int flags)63 openpam_dispatch(pam_handle_t *pamh,
64 int primitive,
65 int flags)
66 {
67 pam_chain_t *chain;
68 int err, fail, nsuccess, r;
69 int debug;
70
71 ENTER();
72
73 /* prevent recursion */
74 if (pamh->current != NULL) {
75 openpam_log(PAM_LOG_ERROR,
76 "%s() called while %s::%s() is in progress",
77 pam_func_name[primitive],
78 pamh->current->module->path,
79 pam_sm_func_name[pamh->primitive]);
80 RETURNC(PAM_ABORT);
81 }
82
83 /* pick a chain */
84 switch (primitive) {
85 case PAM_SM_AUTHENTICATE:
86 case PAM_SM_SETCRED:
87 chain = pamh->chains[PAM_AUTH];
88 break;
89 case PAM_SM_ACCT_MGMT:
90 chain = pamh->chains[PAM_ACCOUNT];
91 break;
92 case PAM_SM_OPEN_SESSION:
93 case PAM_SM_CLOSE_SESSION:
94 chain = pamh->chains[PAM_SESSION];
95 break;
96 case PAM_SM_CHAUTHTOK:
97 chain = pamh->chains[PAM_PASSWORD];
98 break;
99 default:
100 RETURNC(PAM_SYSTEM_ERR);
101 }
102
103 /* execute */
104 err = PAM_SUCCESS;
105 fail = nsuccess = 0;
106 for (; chain != NULL; chain = chain->next) {
107 if (chain->module->func[primitive] == NULL) {
108 openpam_log(PAM_LOG_ERROR, "%s: no %s()",
109 chain->module->path, pam_sm_func_name[primitive]);
110 r = PAM_SYMBOL_ERR;
111 } else {
112 pamh->primitive = primitive;
113 pamh->current = chain;
114 debug = (openpam_get_option(pamh, "debug") != NULL);
115 if (debug)
116 ++openpam_debug;
117 openpam_log(PAM_LOG_LIBDEBUG, "calling %s() in %s",
118 pam_sm_func_name[primitive], chain->module->path);
119 r = (chain->module->func[primitive])(pamh, flags,
120 chain->optc, (const char **)(intptr_t)chain->optv);
121 pamh->current = NULL;
122 openpam_log(PAM_LOG_LIBDEBUG, "%s: %s(): %s",
123 chain->module->path, pam_sm_func_name[primitive],
124 pam_strerror(pamh, r));
125 if (debug)
126 --openpam_debug;
127 }
128
129 if (r == PAM_IGNORE)
130 continue;
131 if (r == PAM_SUCCESS) {
132 ++nsuccess;
133 /*
134 * For pam_setcred() and pam_chauthtok() with the
135 * PAM_PRELIM_CHECK flag, treat "sufficient" as
136 * "optional".
137 */
138 if ((chain->flag == PAM_SUFFICIENT ||
139 chain->flag == PAM_BINDING) && !fail &&
140 primitive != PAM_SM_SETCRED &&
141 !(primitive == PAM_SM_CHAUTHTOK &&
142 (flags & PAM_PRELIM_CHECK)))
143 break;
144 continue;
145 }
146
147 openpam_check_error_code(primitive, r);
148
149 /*
150 * Record the return code from the first module to
151 * fail. If a required module fails, record the
152 * return code from the first required module to fail.
153 */
154 if (err == PAM_SUCCESS)
155 err = r;
156 if ((chain->flag == PAM_REQUIRED ||
157 chain->flag == PAM_BINDING) && !fail) {
158 openpam_log(PAM_LOG_LIBDEBUG, "required module failed");
159 fail = 1;
160 err = r;
161 }
162
163 /*
164 * If a requisite module fails, terminate the chain
165 * immediately.
166 */
167 if (chain->flag == PAM_REQUISITE) {
168 openpam_log(PAM_LOG_LIBDEBUG, "requisite module failed");
169 fail = 1;
170 break;
171 }
172 }
173
174 if (!fail && err != PAM_NEW_AUTHTOK_REQD)
175 err = PAM_SUCCESS;
176
177 /*
178 * Require the chain to be non-empty, and at least one module
179 * in the chain to be successful, so that we don't fail open.
180 */
181 if (err == PAM_SUCCESS && nsuccess < 1) {
182 openpam_log(PAM_LOG_ERROR,
183 "all modules were unsuccessful for %s()",
184 pam_sm_func_name[primitive]);
185 err = PAM_SYSTEM_ERR;
186 }
187
188 RETURNC(err);
189 }
190
191 #if !defined(OPENPAM_RELAX_CHECKS)
192 static void
openpam_check_error_code(int primitive,int r)193 openpam_check_error_code(int primitive, int r)
194 {
195 /* common error codes */
196 if (r == PAM_SUCCESS ||
197 r == PAM_SYSTEM_ERR ||
198 r == PAM_SERVICE_ERR ||
199 r == PAM_BUF_ERR ||
200 r == PAM_CONV_ERR ||
201 r == PAM_PERM_DENIED ||
202 r == PAM_ABORT)
203 return;
204
205 /* specific error codes */
206 switch (primitive) {
207 case PAM_SM_AUTHENTICATE:
208 if (r == PAM_AUTH_ERR ||
209 r == PAM_CRED_INSUFFICIENT ||
210 r == PAM_AUTHINFO_UNAVAIL ||
211 r == PAM_USER_UNKNOWN ||
212 r == PAM_MAXTRIES)
213 return;
214 break;
215 case PAM_SM_SETCRED:
216 if (r == PAM_CRED_UNAVAIL ||
217 r == PAM_CRED_EXPIRED ||
218 r == PAM_USER_UNKNOWN ||
219 r == PAM_CRED_ERR)
220 return;
221 break;
222 case PAM_SM_ACCT_MGMT:
223 if (r == PAM_USER_UNKNOWN ||
224 r == PAM_AUTH_ERR ||
225 r == PAM_NEW_AUTHTOK_REQD ||
226 r == PAM_ACCT_EXPIRED)
227 return;
228 break;
229 case PAM_SM_OPEN_SESSION:
230 case PAM_SM_CLOSE_SESSION:
231 if (r == PAM_SESSION_ERR)
232 return;
233 break;
234 case PAM_SM_CHAUTHTOK:
235 if (r == PAM_PERM_DENIED ||
236 r == PAM_AUTHTOK_ERR ||
237 r == PAM_AUTHTOK_RECOVERY_ERR ||
238 r == PAM_AUTHTOK_LOCK_BUSY ||
239 r == PAM_AUTHTOK_DISABLE_AGING ||
240 r == PAM_TRY_AGAIN)
241 return;
242 break;
243 }
244
245 openpam_log(PAM_LOG_ERROR, "%s(): unexpected return value %d",
246 pam_sm_func_name[primitive], r);
247 }
248 #endif /* !defined(OPENPAM_RELAX_CHECKS) */
249
250 /*
251 * NODOC
252 *
253 * Error codes:
254 */
255