vm: reduce noise in merged pagetable.c
[minix.git] / usr.bin / login / login_pam.c
blob39e0e8247b1b300460fe1f9af0597adbab149ab3
1 /* $NetBSD: login_pam.c,v 1.20 2009/12/29 19:26:13 christos Exp $ */
3 /*-
4 * Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994\
35 The Regents of the University of California. All rights reserved.");
36 #endif /* not lint */
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)login.c 8.4 (Berkeley) 4/2/94";
41 #endif
42 __RCSID("$NetBSD: login_pam.c,v 1.20 2009/12/29 19:26:13 christos Exp $");
43 #endif /* not lint */
46 * login [ name ]
47 * login -h hostname (for telnetd, etc.)
48 * login -f name (for pre-authenticated login: datakit, xterm, etc.)
51 #include <sys/param.h>
52 #include <sys/stat.h>
53 #include <sys/time.h>
54 #include <sys/resource.h>
55 #include <sys/file.h>
56 #include <sys/wait.h>
57 #include <sys/socket.h>
59 #include <err.h>
60 #include <errno.h>
61 #include <grp.h>
62 #include <pwd.h>
63 #include <setjmp.h>
64 #include <signal.h>
65 #include <stdio.h>
66 #include <stdlib.h>
67 #include <string.h>
68 #include <syslog.h>
69 #include <time.h>
70 #include <ttyent.h>
71 #include <tzfile.h>
72 #include <unistd.h>
73 #include <util.h>
74 #include <login_cap.h>
75 #include <vis.h>
77 #include <security/pam_appl.h>
78 #include <security/openpam.h>
80 #include "pathnames.h"
81 #include "common.h"
83 #if 0
84 static int rootterm(char *);
85 #endif
86 static void usage(void) __attribute__((__noreturn__));
88 static struct pam_conv pamc = { openpam_ttyconv, NULL };
90 #define TTYGRPNAME "tty" /* name of group to own ttys */
92 #define DEFAULT_BACKOFF 3
93 #define DEFAULT_RETRIES 10
95 static struct passwd pwres;
96 static char pwbuf[1024];
97 static struct group grs, *grp;
98 static char grbuf[1024];
99 extern char **environ;
102 main(int argc, char *argv[])
104 struct stat st;
105 int ask, ch, cnt, fflag, pflag, quietlog, rootlogin;
106 int auth_passed;
107 uid_t uid, saved_uid;
108 gid_t saved_gid, saved_gids[NGROUPS_MAX];
109 int nsaved_gids;
110 char *domain, *p, *ttyn, *pwprompt;
111 char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10];
112 char localhost[MAXHOSTNAMELEN + 1];
113 int need_chpass, require_chpass;
114 int login_retries = DEFAULT_RETRIES,
115 login_backoff = DEFAULT_BACKOFF;
116 char *shell = NULL;
117 login_cap_t *lc = NULL;
118 pam_handle_t *pamh = NULL;
119 int pam_err;
120 sig_t oint, oabrt, oquit, oalrm;
121 const void *newuser;
122 int pam_silent = PAM_SILENT;
123 pid_t xpid, pid;
124 int status;
125 char *saved_term;
126 char **pamenv;
128 tbuf[0] = '\0';
129 pwprompt = NULL;
130 nested = NULL;
131 need_chpass = require_chpass = 0;
133 oabrt = signal(SIGABRT, SIG_IGN);
134 oalrm = signal(SIGALRM, timedout);
135 oint = signal(SIGINT, SIG_IGN);
136 oquit = signal(SIGQUIT, SIG_IGN);
138 (void)alarm(timeout);
139 (void)setpriority(PRIO_PROCESS, 0, 0);
141 openlog("login", 0, LOG_AUTH);
144 * -p is used by getty to tell login not to destroy the environment
145 * -f is used to skip a second login authentication
146 * -h is used by other servers to pass the name of the remote host to
147 * login so that it may be placed in utmp/utmpx and wtmp/wtmpx
148 * -a in addition to -h, a server my supply -a to pass the actual
149 * server address.
151 domain = NULL;
152 if (gethostname(localhost, sizeof(localhost)) < 0)
153 syslog(LOG_ERR, "couldn't get local hostname: %m");
154 else
155 domain = strchr(localhost, '.');
156 localhost[sizeof(localhost) - 1] = '\0';
158 fflag = pflag = 0;
159 have_ss = 0;
160 uid = getuid();
161 while ((ch = getopt(argc, argv, "a:fh:p")) != -1)
162 switch (ch) {
163 case 'a':
164 if (uid) {
165 errno = EPERM;
166 err(EXIT_FAILURE, "-a option");
168 decode_ss(optarg);
169 break;
170 case 'f':
171 fflag = 1;
172 break;
173 case 'h':
174 if (uid) {
175 errno = EPERM;
176 err(EXIT_FAILURE, "-h option");
178 if (domain && (p = strchr(optarg, '.')) != NULL &&
179 strcasecmp(p, domain) == 0)
180 *p = '\0';
181 hostname = optarg;
182 break;
183 case 'p':
184 pflag = 1;
185 break;
186 default:
187 case '?':
188 usage();
189 break;
192 setproctitle(NULL);
193 argc -= optind;
194 argv += optind;
196 if (*argv) {
197 username = *argv;
198 ask = 0;
199 } else
200 ask = 1;
202 #ifdef F_CLOSEM
203 (void)fcntl(3, F_CLOSEM, 0);
204 #else
205 for (cnt = getdtablesize(); cnt > 2; cnt--)
206 (void)close(cnt);
207 #endif
209 ttyn = ttyname(STDIN_FILENO);
210 if (ttyn == NULL || *ttyn == '\0') {
211 (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY);
212 ttyn = tname;
214 if ((tty = strstr(ttyn, "/pts/")) != NULL)
215 ++tty;
216 else if ((tty = strrchr(ttyn, '/')) != NULL)
217 ++tty;
218 else
219 tty = ttyn;
221 if (issetugid()) {
222 nested = strdup(user_from_uid(getuid(), 0));
223 if (nested == NULL) {
224 syslog(LOG_ERR, "strdup: %m");
225 sleepexit(EXIT_FAILURE);
229 /* Get "login-retries" and "login-backoff" from default class */
230 if ((lc = login_getclass(NULL)) != NULL) {
231 login_retries = (int)login_getcapnum(lc, "login-retries",
232 DEFAULT_RETRIES, DEFAULT_RETRIES);
233 login_backoff = (int)login_getcapnum(lc, "login-backoff",
234 DEFAULT_BACKOFF, DEFAULT_BACKOFF);
235 login_close(lc);
236 lc = NULL;
240 for (cnt = 0;; ask = 1) {
241 if (ask) {
242 fflag = 0;
243 getloginname();
245 rootlogin = 0;
246 auth_passed = 0;
247 if (strlen(username) > MAXLOGNAME)
248 username[MAXLOGNAME] = '\0';
251 * Note if trying multiple user names; log failures for
252 * previous user name, but don't bother logging one failure
253 * for nonexistent name (mistyped username).
255 if (failures && strcmp(tbuf, username)) {
256 if (failures > (pwd ? 0 : 1))
257 badlogin(tbuf);
258 failures = 0;
261 #define PAM_END(msg) do { \
262 syslog(LOG_ERR, "%s: %s", msg, pam_strerror(pamh, pam_err)); \
263 warnx("%s: %s", msg, pam_strerror(pamh, pam_err)); \
264 pam_end(pamh, pam_err); \
265 sleepexit(EXIT_FAILURE); \
266 } while (/*CONSTCOND*/0)
268 pam_err = pam_start("login", username, &pamc, &pamh);
269 if (pam_err != PAM_SUCCESS) {
270 if (pamh != NULL)
271 PAM_END("pam_start");
272 /* Things went really bad... */
273 syslog(LOG_ERR, "pam_start failed: %s",
274 pam_strerror(pamh, pam_err));
275 errx(EXIT_FAILURE, "pam_start failed");
278 #define PAM_SET_ITEM(item, var) do { \
279 pam_err = pam_set_item(pamh, (item), (var)); \
280 if (pam_err != PAM_SUCCESS) \
281 PAM_END("pam_set_item(" # item ")"); \
282 } while (/*CONSTCOND*/0)
285 * Fill hostname tty, and nested user
287 PAM_SET_ITEM(PAM_RHOST, hostname);
288 PAM_SET_ITEM(PAM_TTY, tty);
289 if (nested)
290 PAM_SET_ITEM(PAM_NUSER, nested);
291 if (have_ss)
292 PAM_SET_ITEM(PAM_SOCKADDR, &ss);
295 * Don't check for errors, because we don't want to give
296 * out any information.
298 pwd = NULL;
299 (void)getpwnam_r(username, &pwres, pwbuf, sizeof(pwbuf), &pwd);
302 * Establish the class now, before we might goto
303 * within the next block. pwd can be NULL since it
304 * falls back to the "default" class if it is.
306 lc = login_getclass(pwd ? pwd->pw_class : NULL);
309 * if we have a valid account name, and it doesn't have a
310 * password, or the -f option was specified and the caller
311 * is root or the caller isn't changing their uid, don't
312 * authenticate.
314 if (pwd) {
315 if (pwd->pw_uid == 0)
316 rootlogin = 1;
318 if (fflag && (uid == 0 || uid == pwd->pw_uid)) {
319 /* already authenticated */
320 auth_passed = 1;
321 goto skip_auth;
325 (void)setpriority(PRIO_PROCESS, 0, -4);
327 switch(pam_err = pam_authenticate(pamh, pam_silent)) {
328 case PAM_SUCCESS:
330 * PAM can change the user, refresh
331 * username, pwd, and lc.
333 pam_err = pam_get_item(pamh, PAM_USER, &newuser);
334 if (pam_err != PAM_SUCCESS)
335 PAM_END("pam_get_item(PAM_USER)");
337 username = (char *)newuser;
339 * Don't check for errors, because we don't want to give
340 * out any information.
342 pwd = NULL;
343 (void)getpwnam_r(username, &pwres, pwbuf, sizeof(pwbuf),
344 &pwd);
345 lc = login_getpwclass(pwd);
346 auth_passed = 1;
348 switch (pam_err = pam_acct_mgmt(pamh, pam_silent)) {
349 case PAM_SUCCESS:
350 break;
352 case PAM_NEW_AUTHTOK_REQD:
353 pam_err = pam_chauthtok(pamh,
354 pam_silent|PAM_CHANGE_EXPIRED_AUTHTOK);
356 if (pam_err != PAM_SUCCESS)
357 PAM_END("pam_chauthtok");
358 break;
360 case PAM_AUTH_ERR:
361 case PAM_USER_UNKNOWN:
362 case PAM_MAXTRIES:
363 auth_passed = 0;
364 break;
366 default:
367 PAM_END("pam_acct_mgmt");
368 break;
370 break;
372 case PAM_AUTH_ERR:
373 case PAM_USER_UNKNOWN:
374 case PAM_MAXTRIES:
375 auth_passed = 0;
376 break;
378 default:
379 PAM_END("pam_authenticate");
380 break;
383 (void)setpriority(PRIO_PROCESS, 0, 0);
385 skip_auth:
387 * If the user exists and authentication passed,
388 * get out of the loop and login the user.
390 if (pwd && auth_passed)
391 break;
393 (void)printf("Login incorrect or refused on this terminal.\n");
394 failures++;
395 cnt++;
397 * We allow login_retries tries, but after login_backoff
398 * we start backing off. These default to 10 and 3
399 * respectively.
401 if (cnt > login_backoff) {
402 if (cnt >= login_retries) {
403 badlogin(username);
404 pam_end(pamh, PAM_SUCCESS);
405 sleepexit(EXIT_FAILURE);
407 sleep((u_int)((cnt - login_backoff) * 5));
411 /* committed to login -- turn off timeout */
412 (void)alarm((u_int)0);
414 endpwent();
416 quietlog = login_getcapbool(lc, "hushlogin", 0);
419 * Temporarily give up special privileges so we can change
420 * into NFS-mounted homes that are exported for non-root
421 * access and have mode 7x0
423 saved_uid = geteuid();
424 saved_gid = getegid();
425 nsaved_gids = getgroups(NGROUPS_MAX, saved_gids);
427 (void)setegid(pwd->pw_gid);
428 initgroups(username, pwd->pw_gid);
429 (void)seteuid(pwd->pw_uid);
431 if (chdir(pwd->pw_dir) != 0) {
432 if (login_getcapbool(lc, "requirehome", 0)) {
433 (void)printf("Home directory %s required\n",
434 pwd->pw_dir);
435 pam_end(pamh, PAM_SUCCESS);
436 exit(EXIT_FAILURE);
439 (void)printf("No home directory %s!\n", pwd->pw_dir);
440 if (chdir("/") == -1) {
441 pam_end(pamh, PAM_SUCCESS);
442 exit(EXIT_FAILURE);
444 pwd->pw_dir = "/";
445 (void)printf("Logging in with home = \"/\".\n");
448 if (!quietlog) {
449 quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0;
450 pam_silent = quietlog ? PAM_SILENT : 0;
453 /* regain special privileges */
454 setegid(saved_gid);
455 setgroups(nsaved_gids, saved_gids);
456 seteuid(saved_uid);
458 (void)getgrnam_r(TTYGRPNAME, &grs, grbuf, sizeof(grbuf), &grp);
459 (void)chown(ttyn, pwd->pw_uid,
460 (grp != NULL) ? grp->gr_gid : pwd->pw_gid);
462 if (ttyaction(ttyn, "login", pwd->pw_name))
463 (void)printf("Warning: ttyaction failed.\n");
465 /* Nothing else left to fail -- really log in. */
466 update_db(quietlog, rootlogin, fflag);
468 if (nested == NULL && setusercontext(lc, pwd, pwd->pw_uid,
469 LOGIN_SETLOGIN) != 0) {
470 syslog(LOG_ERR, "setusercontext failed");
471 pam_end(pamh, PAM_SUCCESS);
472 exit(EXIT_FAILURE);
475 if (tty[sizeof("tty")-1] == 'd')
476 syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name);
480 * Establish groups
482 if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETGROUP) != 0) {
483 syslog(LOG_ERR, "setusercontext failed");
484 pam_end(pamh, PAM_SUCCESS);
485 exit(EXIT_FAILURE);
488 pam_err = pam_setcred(pamh, pam_silent|PAM_ESTABLISH_CRED);
489 if (pam_err != PAM_SUCCESS)
490 PAM_END("pam_setcred");
492 pam_err = pam_open_session(pamh, pam_silent);
493 if (pam_err != PAM_SUCCESS)
494 PAM_END("pam_open_session");
497 * Fork because we need to call pam_closesession as root.
498 * Make sure signals cannot kill the parent.
499 * This has been handled in the begining of main.
502 switch(pid = fork()) {
503 case -1:
504 pam_err = pam_close_session(pamh, 0);
505 if (pam_err != PAM_SUCCESS) {
506 syslog(LOG_ERR, "pam_close_session: %s",
507 pam_strerror(pamh, pam_err));
508 warnx("pam_close_session: %s",
509 pam_strerror(pamh, pam_err));
511 syslog(LOG_ERR, "fork failed: %m");
512 warn("fork failed");
513 pam_end(pamh, pam_err);
514 exit(EXIT_FAILURE);
515 break;
517 case 0: /* Child */
518 break;
520 default:
522 * Parent: wait for the child to terminate
523 * and call pam_close_session.
525 if ((xpid = waitpid(pid, &status, 0)) != pid) {
526 pam_err = pam_close_session(pamh, 0);
527 if (pam_err != PAM_SUCCESS) {
528 syslog(LOG_ERR,
529 "pam_close_session: %s",
530 pam_strerror(pamh, pam_err));
531 warnx("pam_close_session: %s",
532 pam_strerror(pamh, pam_err));
534 pam_end(pamh, pam_err);
535 if (xpid != -1)
536 warnx("wrong PID: %d != %d", pid, xpid);
537 else
538 warn("wait for pid %d failed", pid);
539 exit(EXIT_FAILURE);
542 (void)signal(SIGABRT, oabrt);
543 (void)signal(SIGALRM, oalrm);
544 (void)signal(SIGINT, oint);
545 (void)signal(SIGQUIT, oquit);
546 if ((pam_err = pam_close_session(pamh, 0)) != PAM_SUCCESS) {
547 syslog(LOG_ERR, "pam_close_session: %s",
548 pam_strerror(pamh, pam_err));
549 warnx("pam_close_session: %s",
550 pam_strerror(pamh, pam_err));
552 pam_end(pamh, PAM_SUCCESS);
553 exit(EXIT_SUCCESS);
554 break;
558 * The child: starting here, we don't have to care about
559 * handling PAM issues if we exit, the parent will do the
560 * job when we exit.
562 * Destroy environment unless user has requested its preservation.
563 * Try to preserve TERM anyway.
565 saved_term = getenv("TERM");
566 if (!pflag) {
567 environ = envinit;
568 if (saved_term)
569 setenv("TERM", saved_term, 0);
572 if (*pwd->pw_shell == '\0')
573 pwd->pw_shell = _PATH_BSHELL;
575 shell = login_getcapstr(lc, "shell", pwd->pw_shell, pwd->pw_shell);
576 if (*shell == '\0')
577 shell = pwd->pw_shell;
579 if ((pwd->pw_shell = strdup(shell)) == NULL) {
580 syslog(LOG_ERR, "Cannot alloc mem");
581 exit(EXIT_FAILURE);
584 (void)setenv("HOME", pwd->pw_dir, 1);
585 (void)setenv("SHELL", pwd->pw_shell, 1);
586 if (term[0] == '\0') {
587 char *tt = (char *)stypeof(tty);
589 if (tt == NULL)
590 tt = login_getcapstr(lc, "term", NULL, NULL);
592 /* unknown term -> "su" */
593 (void)strlcpy(term, tt != NULL ? tt : "su", sizeof(term));
595 (void)setenv("TERM", term, 0);
596 (void)setenv("LOGNAME", pwd->pw_name, 1);
597 (void)setenv("USER", pwd->pw_name, 1);
600 * Add PAM environement
602 if ((pamenv = pam_getenvlist(pamh)) != NULL) {
603 char **envitem;
605 for (envitem = pamenv; *envitem; envitem++) {
606 putenv(*envitem);
607 free(*envitem);
610 free(pamenv);
613 /* This drops root privs */
614 if (setusercontext(lc, pwd, pwd->pw_uid,
615 (LOGIN_SETALL & ~LOGIN_SETLOGIN)) != 0) {
616 syslog(LOG_ERR, "setusercontext failed");
617 exit(EXIT_FAILURE);
620 if (!quietlog) {
621 char *fname;
623 fname = login_getcapstr(lc, "copyright", NULL, NULL);
624 if (fname != NULL && access(fname, F_OK) == 0)
625 motd(fname);
626 else
627 (void)printf("%s", copyrightstr);
629 fname = login_getcapstr(lc, "welcome", NULL, NULL);
630 if (fname == NULL || access(fname, F_OK) != 0)
631 fname = _PATH_MOTDFILE;
632 motd(fname);
634 (void)snprintf(tbuf,
635 sizeof(tbuf), "%s/%s", _PATH_MAILDIR, pwd->pw_name);
636 if (stat(tbuf, &st) == 0 && st.st_size != 0)
637 (void)printf("You have %smail.\n",
638 (st.st_mtime > st.st_atime) ? "new " : "");
641 login_close(lc);
644 tbuf[0] = '-';
645 (void)strlcpy(tbuf + 1, (p = strrchr(pwd->pw_shell, '/')) ?
646 p + 1 : pwd->pw_shell, sizeof(tbuf) - 1);
648 (void)signal(SIGABRT, oabrt);
649 (void)signal(SIGALRM, oalrm);
650 (void)signal(SIGINT, oint);
651 (void)signal(SIGQUIT, oquit);
652 (void)signal(SIGTSTP, SIG_IGN);
654 execlp(pwd->pw_shell, tbuf, NULL);
655 err(EXIT_FAILURE, "%s", pwd->pw_shell);
658 static void
659 usage(void)
661 (void)fprintf(stderr,
662 "Usage: %s [-fp] [-a address] [-h hostname] [username]\n",
663 getprogname());
664 exit(EXIT_FAILURE);
667 #if 0
668 static int
669 rootterm(char *ttyn)
671 struct ttyent *t;
673 return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE);
675 #endif