1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26
27 #include <stdlib.h>
28 #include <pwd.h>
29 #include <shadow.h>
30 #include <syslog.h>
31 #include <errno.h>
32 #include <string.h>
33 #include <crypt.h>
34 #include <unistd.h>
35 #include <user_attr.h>
36 #include <auth_attr.h>
37 #include <userdefs.h>
38 #include <deflt.h>
39 #include <sys/stat.h>
40 #include <sys/param.h>
41 #include <stdarg.h>
42
43 #include <security/pam_appl.h>
44 #include <security/pam_modules.h>
45 #include <security/pam_impl.h>
46
47 #include <libintl.h>
48
49 #include <passwdutil.h>
50
51 #define LOGINADMIN "/etc/default/login"
52 #define MAXTRYS 5
53
54 /*PRINTFLIKE2*/
55 void
56 error(pam_handle_t *pamh, char *fmt, ...)
57 {
58 va_list ap;
59 char messages[1][PAM_MAX_MSG_SIZE];
60
61 va_start(ap, fmt);
62 (void) vsnprintf(messages[0], sizeof (messages[0]), fmt, ap);
63 (void) __pam_display_msg(pamh, PAM_ERROR_MSG, 1, messages, NULL);
64 va_end(ap);
65 }
66
67 static int
68 get_max_failed(char *user)
69 {
70 char *val = NULL;
71 userattr_t *uattr;
72 int do_lock = 0;
73 int retval = 0;
74 char *p;
75 void *defp;
76
77 if ((uattr = getusernam(user)) != NULL)
78 val = kva_match(uattr->attr, USERATTR_LOCK_AFTER_RETRIES_KW);
79
80 if (val != NULL) {
81 do_lock = (strcasecmp(val, "yes") == 0);
82 } else if ((defp = defopen_r(AUTH_POLICY)) != NULL) {
83 int flags;
84 flags = defcntl_r(DC_GETFLAGS, 0, defp);
85 TURNOFF(flags, DC_CASE);
86 (void) defcntl_r(DC_SETFLAGS, flags, defp);
87 if ((p = defread_r("LOCK_AFTER_RETRIES=", defp)) != NULL)
88 do_lock = (strcasecmp(p, "yes") == 0);
89 defclose_r(defp);
90 }
91
92 if (uattr != NULL)
93 free_userattr(uattr);
94
95 if (do_lock) {
96 retval = MAXTRYS;
97 if ((defp = defopen_r(LOGINADMIN)) != NULL) {
98 if ((p = defread_r("RETRIES=", defp)) != NULL)
99 retval = atoi(p);
100 defclose_r(defp);
101 }
102 }
103
104 return (retval);
105 }
106
107 static void
108 display_warning(pam_handle_t *pamh, int failures, char *homedir)
109 {
110 char hushpath[MAXPATHLEN];
111 struct stat buf;
112
113 (void) snprintf(hushpath, sizeof (hushpath), "%s/.hushlogin", homedir);
114 if (stat(hushpath, &buf) == 0)
115 return;
116
117 if (failures == 1)
118 error(pamh, "Warning: 1 failed login attempt since last "
119 "successful login.");
120 else if (failures < FAILCOUNT_MASK)
121 error(pamh, "Warning: %d failed login attempts since last "
122 "successful login.", failures);
123 else
124 error(pamh, "Warning: at least %d failed login attempts since "
125 "last successful login.", failures);
126 }
127
128 /*
129 * int pam_sm_authenticate(pamh, flags, arc, argv)
130 *
131 * This routine verifies that the password as stored in the
132 * PAM_AUTHTOK item is indeed the password that belongs to the user
133 * as stored in PAM_USER.
134 *
135 * This routine will not establish Secure RPC Credentials, the pam_dhkeys
136 * module should be stacked before us if Secure RPC Credentials are needed
137 * to obtain passwords.
138 */
139 int
140 pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc, const char **argv)
141 {
142 int i;
143 int debug = 0;
144 int nowarn = (flags & PAM_SILENT) != 0;
145 char *user;
146 char *passwd;
147 char *rep_passwd;
148 char *crypt_passwd;
149 char *repository_name;
150 struct pam_repository *auth_rep;
151 pwu_repository_t *pwu_rep;
152 attrlist attr_pw[4];
153 int result;
154 int server_policy = 0;
155 int old_failed_count;
156 char *homedir = NULL;
157 int dolock = 1;
158
159 for (i = 0; i < argc; i++) {
160 if (strcmp(argv[i], "debug") == 0)
161 debug = 1;
162 else if (strcmp(argv[i], "nowarn") == 0)
163 nowarn = 1;
164 else if (strcmp(argv[i], "server_policy") == 0)
165 server_policy = 1;
166 else if (strcmp(argv[i], "nolock") == 0)
167 dolock = 0;
168 }
169
170 if (debug)
171 __pam_log(LOG_AUTH | LOG_DEBUG,
172 "pam_unix_auth: entering pam_sm_authenticate()");
173
174 if (pam_get_item(pamh, PAM_USER, (void **)&user) != PAM_SUCCESS) {
175 __pam_log(LOG_AUTH | LOG_DEBUG, "pam_unix_auth: USER not set");
176 return (PAM_SYSTEM_ERR);
177 }
178
179 if (user == NULL || *user == '\0') {
180 __pam_log(LOG_AUTH | LOG_DEBUG,
181 "pam_unix_auth: USER NULL or empty!\n");
182 return (PAM_USER_UNKNOWN);
183 }
184
185 if (pam_get_item(pamh, PAM_AUTHTOK, (void **)&passwd) != PAM_SUCCESS) {
186 __pam_log(LOG_AUTH | LOG_DEBUG,
187 "pam_unix_auth: AUTHTOK not set!\n");
188 return (PAM_SYSTEM_ERR);
189 }
190
191 result = pam_get_item(pamh, PAM_REPOSITORY, (void **)&auth_rep);
192 if (result == PAM_SUCCESS && auth_rep != NULL) {
193 if ((pwu_rep = calloc(1, sizeof (*pwu_rep))) == NULL)
194 return (PAM_BUF_ERR);
195 pwu_rep->type = auth_rep->type;
196 pwu_rep->scope = auth_rep->scope;
197 pwu_rep->scope_len = auth_rep->scope_len;
198 } else {
199 pwu_rep = PWU_DEFAULT_REP;
200 }
201
202 /*
203 * Get password and the name of the repository where the
204 * password resides.
205 */
206 attr_pw[0].type = ATTR_PASSWD; attr_pw[0].next = &attr_pw[1];
207 attr_pw[1].type = ATTR_REP_NAME; attr_pw[1].next = &attr_pw[2];
208 /*
209 * Also get the current number of failed logins; we use
210 * this later to determine whether we need to reset the count
211 * on a succesful authentication. We use the home-directory
212 * to look for .hushlogin in order to optionaly surpress the
213 * "failed attempts" message.
214 */
215 attr_pw[2].type = ATTR_FAILED_LOGINS; attr_pw[2].next = &attr_pw[3];
216 attr_pw[3].type = ATTR_HOMEDIR; attr_pw[3].next = NULL;
217
218 result = __get_authtoken_attr(user, pwu_rep, attr_pw);
219
220 if (pwu_rep != PWU_DEFAULT_REP)
221 free(pwu_rep);
222
223 if (result == PWU_NOT_FOUND) {
224 __pam_log(LOG_AUTH | LOG_DEBUG,
225 "pam_unix_auth: user %s not found\n", user);
226 return (PAM_USER_UNKNOWN);
227 }
228
229 if (result == PWU_DENIED) {
230 __pam_log(LOG_AUTH | LOG_DEBUG,
231 "pam_unix_auth: failed to obtain attributes");
232 return (PAM_PERM_DENIED);
233 }
234
235 if (result != PWU_SUCCESS)
236 return (PAM_SYSTEM_ERR);
237
238 rep_passwd = attr_pw[0].data.val_s;
239 repository_name = attr_pw[1].data.val_s;
240 old_failed_count = attr_pw[2].data.val_i;
241 homedir = attr_pw[3].data.val_s;
242
243 /*
244 * Chop off old SunOS-style password aging information.
245 *
246 * Note: old style password aging is only defined for UNIX-style
247 * crypt strings, hence the comma will always be at position 14.
248 * Note: This code is here because some other vendors might still
249 * support this style of password aging. If we don't remove
250 * the age field, no one will be able to login.
251 * XXX yank this code when we're certain this "compatibility"
252 * isn't needed anymore.
253 */
254 if (rep_passwd != NULL && rep_passwd[0] != '$' &&
255 strlen(rep_passwd) > 13 && rep_passwd[13] == ',')
256 rep_passwd[13] = '\0';
257
258 /* Is a password check required? */
259 if (rep_passwd == NULL || *rep_passwd == '\0') {
260 if (flags & PAM_DISALLOW_NULL_AUTHTOK) {
261 result = PAM_AUTH_ERR;
262 __pam_log(LOG_AUTH | LOG_NOTICE,
263 "pam_unix_auth: empty password for %s not allowed.",
264 user);
265 goto out;
266 } else {
267 result = PAM_SUCCESS;
268 goto out;
269 }
270 }
271
272 /*
273 * Password check *is* required. Make sure we have a valid
274 * pointer in PAM_AUTHTOK
275 */
276 if (passwd == NULL) {
277 result = PAM_AUTH_ERR;
278 goto out;
279 }
280
281 if (server_policy &&
282 strcmp(repository_name, "files") != 0 &&
283 strcmp(repository_name, "nis") != 0) {
284 result = PAM_IGNORE;
285 goto out;
286 }
287
288 /* Now check the entered password */
289 if ((crypt_passwd = crypt(passwd, rep_passwd)) == NULL) {
290 switch (errno) {
291 case ENOMEM:
292 result = PAM_BUF_ERR;
293 break;
294 case ELIBACC:
295 result = PAM_OPEN_ERR;
296 break;
297 default:
298 result = PAM_SYSTEM_ERR;
299 }
300 goto out;
301 }
302
303 if (strcmp(crypt_passwd, rep_passwd) == 0)
304 result = PAM_SUCCESS;
305 else
306 result = PAM_AUTH_ERR;
307
308 /* Clear or increment failed failed count */
309 if (dolock && (result == PAM_SUCCESS && old_failed_count > 0)) {
310 old_failed_count = __rst_failed_count(user, repository_name);
311 if (nowarn == 0 && old_failed_count > 0)
312 display_warning(pamh, old_failed_count, homedir);
313 } else if (dolock && result == PAM_AUTH_ERR) {
314 int max_failed = get_max_failed(user);
315 if (max_failed != 0) {
316 if (__incr_failed_count(user, repository_name,
317 max_failed) == PWU_ACCOUNT_LOCKED)
318 result = PAM_MAXTRIES;
319 }
320 }
321 out:
322 if (rep_passwd)
323 free(rep_passwd);
324 if (repository_name)
325 free(repository_name);
326 if (homedir)
327 free(homedir);
328 return (result);
329 }
330
331 /*ARGSUSED*/
332 int
333 pam_sm_setcred(pam_handle_t *pamh, int flags, int argc, const char **argv)
334 {
335 return (PAM_IGNORE);
336 }