Add sha256/512 support to libcrypt, change default
[dragonfly.git] / lib / pam_module / pam_unix / pam_unix.c
CommitLineData
863a10dd
JS
1/*-
2 * Copyright 1998 Juniper Networks, Inc.
3 * All rights reserved.
4 * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
5 * All rights reserved.
6 *
7 * Portions of this software was developed for the FreeBSD Project by
8 * ThinkSec AS and NAI Labs, the Security Research Division of Network
9 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035
10 * ("CBOSS"), as part of the DARPA CHATS research program.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. The name of the author may not be used to endorse or promote
21 * products derived from this software without specific prior written
22 * permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
0d96fe5a 36 * $FreeBSD: src/lib/libpam/modules/pam_unix/pam_unix.c,v 1.53 2007/12/21 12:00:16 des Exp $
863a10dd
JS
37 * $DragonFly: src/lib/pam_module/pam_unix/pam_unix.c,v 1.1 2005/08/01 16:15:19 joerg Exp $
38 */
39
40#include <sys/param.h>
41#include <sys/socket.h>
42#include <sys/time.h>
43#include <netinet/in.h>
44#include <arpa/inet.h>
45
46#include <login_cap.h>
47#include <netdb.h>
48#include <pwd.h>
49#include <stdlib.h>
50#include <string.h>
51#include <stdio.h>
52#include <syslog.h>
53#include <unistd.h>
54
55#include <libutil.h>
56
57#ifdef YP
58#include <ypclnt.h>
59#endif
60
61#define PAM_SM_AUTH
62#define PAM_SM_ACCOUNT
63#define PAM_SM_PASSWORD
64
65#include <security/pam_appl.h>
66#include <security/pam_modules.h>
67#include <security/pam_mod_misc.h>
68
6737f3b9 69#define PASSWORD_HASH "sha256"
863a10dd
JS
70#define DEFAULT_WARN (2L * 7L * 86400L) /* Two weeks */
71#define SALTSIZE 32
72
0d96fe5a
PA
73#define LOCKED_PREFIX "*LOCKED*"
74#define LOCKED_PREFIX_LEN (sizeof(LOCKED_PREFIX) - 1)
75
863a10dd
JS
76static void makesalt(char []);
77
78static char password_hash[] = PASSWORD_HASH;
79
80#define PAM_OPT_LOCAL_PASS "local_pass"
81#define PAM_OPT_NIS_PASS "nis_pass"
82
83char *tempname = NULL;
84
85/*
86 * authentication management
87 */
88PAM_EXTERN int
89pam_sm_authenticate(pam_handle_t *pamh, int flags __unused,
90 int argc __unused, const char *argv[] __unused)
91{
92 login_cap_t *lc;
93 struct passwd *pwd;
94 int retval;
95 const char *pass, *user, *realpw, *prompt;
96
97 if (openpam_get_option(pamh, PAM_OPT_AUTH_AS_SELF)) {
98 pwd = getpwnam(getlogin());
99 } else {
100 retval = pam_get_user(pamh, &user, NULL);
101 if (retval != PAM_SUCCESS)
102 return (retval);
103 pwd = getpwnam(user);
104 }
105
106 PAM_LOG("Got user: %s", user);
107
108 if (pwd != NULL) {
109 PAM_LOG("Doing real authentication");
110 realpw = pwd->pw_passwd;
111 if (realpw[0] == '\0') {
112 if (!(flags & PAM_DISALLOW_NULL_AUTHTOK) &&
113 openpam_get_option(pamh, PAM_OPT_NULLOK))
114 return (PAM_SUCCESS);
115 realpw = "*";
116 }
117 lc = login_getpwclass(pwd);
118 } else {
119 PAM_LOG("Doing dummy authentication");
120 realpw = "*";
121 lc = login_getclass(NULL);
122 }
123 prompt = login_getcapstr(lc, "passwd_prompt", NULL, NULL);
124 retval = pam_get_authtok(pamh, PAM_AUTHTOK, &pass, prompt);
125 login_close(lc);
126 if (retval != PAM_SUCCESS)
127 return (retval);
128 PAM_LOG("Got password");
129 if (strcmp(crypt(pass, realpw), realpw) == 0)
130 return (PAM_SUCCESS);
131
0d96fe5a 132 PAM_VERBOSE_ERROR("UNIX authentication refused");
863a10dd
JS
133 return (PAM_AUTH_ERR);
134}
135
136PAM_EXTERN int
137pam_sm_setcred(pam_handle_t *pamh __unused, int flags __unused,
138 int argc __unused, const char *argv[] __unused)
139{
140
141 return (PAM_SUCCESS);
142}
143
144/*
145 * account management
146 */
147PAM_EXTERN int
148pam_sm_acct_mgmt(pam_handle_t *pamh, int flags __unused,
149 int argc __unused, const char *argv[] __unused)
150{
151 struct addrinfo hints, *res;
152 struct passwd *pwd;
153 struct timeval tp;
154 login_cap_t *lc;
155 time_t warntime;
156 int retval;
157 const char *user;
158 const void *rhost, *tty;
159 char rhostip[MAXHOSTNAMELEN] = "";
160
161 retval = pam_get_user(pamh, &user, NULL);
162 if (retval != PAM_SUCCESS)
163 return (retval);
164
165 if (user == NULL || (pwd = getpwnam(user)) == NULL)
166 return (PAM_SERVICE_ERR);
167
168 PAM_LOG("Got user: %s", user);
169
170 retval = pam_get_item(pamh, PAM_RHOST, &rhost);
171 if (retval != PAM_SUCCESS)
172 return (retval);
173
174 retval = pam_get_item(pamh, PAM_TTY, &tty);
175 if (retval != PAM_SUCCESS)
176 return (retval);
177
178 if (*pwd->pw_passwd == '\0' &&
179 (flags & PAM_DISALLOW_NULL_AUTHTOK) != 0)
180 return (PAM_NEW_AUTHTOK_REQD);
181
0d96fe5a
PA
182 if (strncmp(pwd->pw_passwd, LOCKED_PREFIX, LOCKED_PREFIX_LEN) == 0)
183 return (PAM_AUTH_ERR);
184
863a10dd
JS
185 lc = login_getpwclass(pwd);
186 if (lc == NULL) {
187 PAM_LOG("Unable to get login class for user %s", user);
188 return (PAM_SERVICE_ERR);
189 }
190
191 PAM_LOG("Got login_cap");
192
193 if (pwd->pw_change || pwd->pw_expire)
194 gettimeofday(&tp, NULL);
195
196 /*
197 * Check pw_expire before pw_change - no point in letting the
198 * user change the password on an expired account.
199 */
200
201 if (pwd->pw_expire) {
202 warntime = login_getcaptime(lc, "warnexpire",
203 DEFAULT_WARN, DEFAULT_WARN);
204 if (tp.tv_sec >= pwd->pw_expire) {
205 login_close(lc);
206 return (PAM_ACCT_EXPIRED);
207 } else if (pwd->pw_expire - tp.tv_sec < warntime &&
208 (flags & PAM_SILENT) == 0) {
209 pam_error(pamh, "Warning: your account expires on %s",
210 ctime(&pwd->pw_expire));
211 }
212 }
213
214 retval = PAM_SUCCESS;
215 if (pwd->pw_change) {
216 warntime = login_getcaptime(lc, "warnpassword",
217 DEFAULT_WARN, DEFAULT_WARN);
218 if (tp.tv_sec >= pwd->pw_change) {
219 retval = PAM_NEW_AUTHTOK_REQD;
220 } else if (pwd->pw_change - tp.tv_sec < warntime &&
221 (flags & PAM_SILENT) == 0) {
222 pam_error(pamh, "Warning: your password expires on %s",
223 ctime(&pwd->pw_change));
224 }
225 }
226
227 /*
228 * From here on, we must leave retval untouched (unless we
229 * know we're going to fail), because we need to remember
230 * whether we're supposed to return PAM_SUCCESS or
231 * PAM_NEW_AUTHTOK_REQD.
232 */
233
234 if (rhost && *(const char *)rhost != '\0') {
235 memset(&hints, 0, sizeof(hints));
236 hints.ai_family = AF_UNSPEC;
237 if (getaddrinfo(rhost, NULL, &hints, &res) == 0) {
238 getnameinfo(res->ai_addr, res->ai_addrlen,
239 rhostip, sizeof(rhostip), NULL, 0,
240 NI_NUMERICHOST);
241 }
242 if (res != NULL)
243 freeaddrinfo(res);
244 }
245
246 /*
247 * Check host / tty / time-of-day restrictions
248 */
249
250 if (!auth_hostok(lc, rhost, rhostip) ||
251 !auth_ttyok(lc, tty) ||
252 !auth_timeok(lc, time(NULL)))
253 retval = PAM_AUTH_ERR;
254
255 login_close(lc);
256
257 return (retval);
258}
259
260/*
261 * password management
262 *
263 * standard Unix and NIS password changing
264 */
265PAM_EXTERN int
266pam_sm_chauthtok(pam_handle_t *pamh, int flags,
267 int argc __unused, const char *argv[] __unused)
268{
269#ifdef YP
270 struct ypclnt *ypclnt;
210bf96c 271 const void *yp_domain, *yp_server;
863a10dd
JS
272#endif
273 char salt[SALTSIZE + 1];
274 login_cap_t * lc;
275 struct passwd *pwd, *old_pwd;
276 const char *user, *old_pass, *new_pass;
277 char *encrypted;
0d96fe5a 278 int pfd, tfd, retval;
863a10dd
JS
279
280 if (openpam_get_option(pamh, PAM_OPT_AUTH_AS_SELF))
281 pwd = getpwnam(getlogin());
282 else {
283 retval = pam_get_user(pamh, &user, NULL);
284 if (retval != PAM_SUCCESS)
285 return (retval);
286 pwd = getpwnam(user);
287 }
288
289 if (pwd == NULL)
290 return (PAM_AUTHTOK_RECOVERY_ERR);
291
292 PAM_LOG("Got user: %s", user);
293
294 if (flags & PAM_PRELIM_CHECK) {
295
296 PAM_LOG("PRELIM round");
297
0d96fe5a
PA
298 if (getuid() == 0 &&
299 (pwd->pw_fields & _PWF_SOURCE) == _PWF_FILES)
863a10dd
JS
300 /* root doesn't need the old password */
301 return (pam_set_item(pamh, PAM_OLDAUTHTOK, ""));
302#ifdef YP
0d96fe5a
PA
303 if (getuid() == 0 &&
304 (pwd->pw_fields & _PWF_SOURCE) == _PWF_NIS) {
863a10dd
JS
305
306 yp_domain = yp_server = NULL;
0d96fe5a
PA
307 pam_get_data(pamh, "yp_domain", &yp_domain);
308 pam_get_data(pamh, "yp_server", &yp_server);
863a10dd
JS
309
310 ypclnt = ypclnt_new(yp_domain, "passwd.byname", yp_server);
311 if (ypclnt == NULL)
312 return (PAM_BUF_ERR);
313
314 if (ypclnt_connect(ypclnt) == -1) {
315 ypclnt_free(ypclnt);
316 return (PAM_SERVICE_ERR);
317 }
318
319 retval = ypclnt_havepasswdd(ypclnt);
320 ypclnt_free(ypclnt);
321 if (retval == 1)
322 return (pam_set_item(pamh, PAM_OLDAUTHTOK, ""));
323 else if (retval == -1)
324 return (PAM_SERVICE_ERR);
325 }
326#endif
327 if (pwd->pw_passwd[0] == '\0'
328 && openpam_get_option(pamh, PAM_OPT_NULLOK)) {
329 /*
330 * No password case. XXX Are we giving too much away
331 * by not prompting for a password?
332 * XXX check PAM_DISALLOW_NULL_AUTHTOK
333 */
334 old_pass = "";
335 } else {
336 retval = pam_get_authtok(pamh,
337 PAM_OLDAUTHTOK, &old_pass, NULL);
338 if (retval != PAM_SUCCESS)
339 return (retval);
340 }
341 PAM_LOG("Got old password");
342 /* always encrypt first */
343 encrypted = crypt(old_pass, pwd->pw_passwd);
344 if (old_pass[0] == '\0' &&
345 !openpam_get_option(pamh, PAM_OPT_NULLOK))
346 return (PAM_PERM_DENIED);
347 if (strcmp(encrypted, pwd->pw_passwd) != 0)
348 return (PAM_PERM_DENIED);
349 }
350 else if (flags & PAM_UPDATE_AUTHTOK) {
351 PAM_LOG("UPDATE round");
352
353 retval = pam_get_authtok(pamh,
354 PAM_OLDAUTHTOK, &old_pass, NULL);
355 if (retval != PAM_SUCCESS)
356 return (retval);
357 PAM_LOG("Got old password");
358
359 /* get new password */
360 for (;;) {
361 retval = pam_get_authtok(pamh,
362 PAM_AUTHTOK, &new_pass, NULL);
363 if (retval != PAM_TRY_AGAIN)
364 break;
365 pam_error(pamh, "Mismatch; try again, EOF to quit.");
366 }
367 PAM_LOG("Got new password");
368 if (retval != PAM_SUCCESS) {
369 PAM_VERBOSE_ERROR("Unable to get new password");
370 return (retval);
371 }
372
373 if (getuid() != 0 && new_pass[0] == '\0' &&
374 !openpam_get_option(pamh, PAM_OPT_NULLOK))
375 return (PAM_PERM_DENIED);
376
377 if ((old_pwd = pw_dup(pwd)) == NULL)
378 return (PAM_BUF_ERR);
379
380 pwd->pw_change = 0;
381 lc = login_getclass(pwd->pw_class);
382 if (login_setcryptfmt(lc, password_hash, NULL) == NULL)
383 openpam_log(PAM_LOG_ERROR,
384 "can't set password cipher, relying on default");
385 login_close(lc);
386 makesalt(salt);
387 pwd->pw_passwd = crypt(new_pass, salt);
388#ifdef YP
389 switch (old_pwd->pw_fields & _PWF_SOURCE) {
390 case _PWF_FILES:
391#endif
392 retval = PAM_SERVICE_ERR;
393 if (pw_init(NULL, NULL))
394 openpam_log(PAM_LOG_ERROR, "pw_init() failed");
395 else if ((pfd = pw_lock()) == -1)
396 openpam_log(PAM_LOG_ERROR, "pw_lock() failed");
397 else if ((tfd = pw_tmp(-1)) == -1)
398 openpam_log(PAM_LOG_ERROR, "pw_tmp() failed");
399 else if (pw_copy(pfd, tfd, pwd, old_pwd) == -1)
400 openpam_log(PAM_LOG_ERROR, "pw_copy() failed");
401 else if (pw_mkdb(pwd->pw_name) == -1)
402 openpam_log(PAM_LOG_ERROR, "pw_mkdb() failed");
403 else
404 retval = PAM_SUCCESS;
405 pw_fini();
406#ifdef YP
407 break;
408 case _PWF_NIS:
409 yp_domain = yp_server = NULL;
0d96fe5a
PA
410 pam_get_data(pamh, "yp_domain", &yp_domain);
411 pam_get_data(pamh, "yp_server", &yp_server);
863a10dd
JS
412 ypclnt = ypclnt_new(yp_domain,
413 "passwd.byname", yp_server);
414 if (ypclnt == NULL) {
415 retval = PAM_BUF_ERR;
416 } else if (ypclnt_connect(ypclnt) == -1 ||
417 ypclnt_passwd(ypclnt, pwd, old_pass) == -1) {
418 openpam_log(PAM_LOG_ERROR, "%s", ypclnt->error);
419 retval = PAM_SERVICE_ERR;
420 } else {
421 retval = PAM_SUCCESS;
422 }
423 ypclnt_free(ypclnt);
424 break;
425 default:
426 openpam_log(PAM_LOG_ERROR, "unsupported source 0x%x",
427 pwd->pw_fields & _PWF_SOURCE);
428 retval = PAM_SERVICE_ERR;
429 }
430#endif
431 free(old_pwd);
432 }
433 else {
434 /* Very bad juju */
435 retval = PAM_ABORT;
436 PAM_LOG("Illegal 'flags'");
437 }
438
439 return (retval);
440}
441
442/* Mostly stolen from passwd(1)'s local_passwd.c - markm */
443
444static unsigned char itoa64[] = /* 0 ... 63 => ascii - 64 */
445 "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
446
447static void
448to64(char *s, long v, int n)
449{
450 while (--n >= 0) {
451 *s++ = itoa64[v&0x3f];
452 v >>= 6;
453 }
454}
455
456/* Salt suitable for traditional DES and MD5 */
457void
458makesalt(char salt[SALTSIZE])
459{
460 int i;
461
462 /* These are not really random numbers, they are just
463 * numbers that change to thwart construction of a
464 * dictionary. This is exposed to the public.
465 */
466 for (i = 0; i < SALTSIZE; i += 4)
467 to64(&salt[i], arc4random(), 4);
468 salt[SALTSIZE] = '\0';
469}
470
471PAM_MODULE_ENTRY("pam_unix");