MFC numerous features from HEAD.
[dragonfly.git] / usr.bin / login / login.c
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1 /*-
2 * Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
33 * @(#)login.c 8.4 (Berkeley) 4/2/94
34 * $FreeBSD: src/usr.bin/login/login.c,v 1.51.2.15 2003/04/29 14:10:41 des Exp $
35 * $DragonFly: src/usr.bin/login/login.c,v 1.6 2006/01/12 13:43:11 corecode Exp $
38 #if 0
39 static char copyright[] =
40 "@(#) Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994\n\
41 The Regents of the University of California. All rights reserved.\n";
42 #endif
45 * login [ name ]
46 * login -h hostname (for telnetd, etc.)
47 * login -f name (for pre-authenticated login: datakit, xterm, etc.)
50 #include <sys/copyright.h>
51 #include <sys/param.h>
52 #include <sys/stat.h>
53 #include <sys/socket.h>
54 #include <sys/time.h>
55 #include <sys/resource.h>
56 #include <sys/file.h>
57 #include <netinet/in.h>
58 #include <arpa/inet.h>
60 #include <err.h>
61 #include <errno.h>
62 #include <grp.h>
63 #include <libutil.h>
64 #include <login_cap.h>
65 #include <netdb.h>
66 #include <pwd.h>
67 #include <setjmp.h>
68 #include <signal.h>
69 #include <stdio.h>
70 #include <stdlib.h>
71 #include <string.h>
72 #include <syslog.h>
73 #include <ttyent.h>
74 #include <unistd.h>
75 #include <utmp.h>
77 #ifdef USE_PAM
78 #include <security/pam_appl.h>
79 #include <security/pam_types.h>
80 #include <security/openpam.h>
81 #include <sys/wait.h>
82 #endif /* USE_PAM */
84 #include "pathnames.h"
86 /* wrapper for KAME-special getnameinfo() */
87 #ifndef NI_WITHSCOPEID
88 #define NI_WITHSCOPEID 0
89 #endif
91 void badlogin(char *);
92 void checknologin(void);
93 void dolastlog(int);
94 void getloginname(void);
95 void motd(char *);
96 int rootterm(char *);
97 void sigint(int);
98 void sleepexit(int);
99 void refused(char *,char *,int);
100 char *stypeof(char *);
101 void timedout(int);
102 int login_access(char *, char *);
103 void login_fbtab(char *, uid_t, gid_t);
105 #ifdef USE_PAM
106 static int auth_pam(void);
107 static int export_pam_environment(void);
108 static int ok_to_export(const char *);
110 static pam_handle_t *pamh = NULL;
111 static char **environ_pam;
113 #define PAM_END { \
114 if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS) \
115 syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e)); \
116 if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS) \
117 syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e)); \
118 if ((e = pam_end(pamh, e)) != PAM_SUCCESS) \
119 syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e)); \
121 #endif /* USE_PAM */
122 static int auth_traditional(void);
123 extern void login(struct utmp *);
124 static void usage(void);
126 #define TTYGRPNAME "tty" /* name of group to own ttys */
127 #define DEFAULT_BACKOFF 3
128 #define DEFAULT_RETRIES 10
129 #define DEFAULT_PROMPT "login: "
130 #define DEFAULT_PASSWD_PROMPT "Password:"
133 * This bounds the time given to login. Not a define so it can
134 * be patched on machines where it's too small.
136 u_int timeout = 300;
138 /* Buffer for signal handling of timeout */
139 jmp_buf timeout_buf;
141 struct passwd *pwd;
142 int failures;
143 char *term, *envinit[1], *hostname, *passwd_prompt, *prompt, *tty, *username;
144 char full_hostname[MAXHOSTNAMELEN];
147 main(int argc, char **argv)
149 extern char **environ;
150 struct group *gr;
151 struct stat st;
152 struct timeval tp;
153 struct utmp utmp;
154 int rootok, retries, backoff;
155 int ask, ch, cnt, fflag, hflag, pflag, quietlog, rootlogin, rval;
156 int changepass;
157 time_t warntime;
158 uid_t uid, euid;
159 gid_t egid;
160 char *p, *ttyn;
161 char tbuf[MAXPATHLEN + 2];
162 char tname[sizeof(_PATH_TTY) + 10];
163 char *shell = NULL;
164 login_cap_t *lc = NULL;
165 #ifdef USE_PAM
166 pid_t pid;
167 int e;
168 #endif /* USE_PAM */
170 (void)signal(SIGQUIT, SIG_IGN);
171 (void)signal(SIGINT, SIG_IGN);
172 (void)signal(SIGHUP, SIG_IGN);
173 if (setjmp(timeout_buf)) {
174 if (failures)
175 badlogin(tbuf);
176 (void)fprintf(stderr, "Login timed out after %d seconds\n",
177 timeout);
178 exit(0);
180 (void)signal(SIGALRM, timedout);
181 (void)alarm(timeout);
182 (void)setpriority(PRIO_PROCESS, 0, 0);
184 openlog("login", LOG_ODELAY, LOG_AUTH);
187 * -p is used by getty to tell login not to destroy the environment
188 * -f is used to skip a second login authentication
189 * -h is used by other servers to pass the name of the remote
190 * host to login so that it may be placed in utmp and wtmp
192 *full_hostname = '\0';
193 term = NULL;
195 fflag = hflag = pflag = 0;
196 uid = getuid();
197 euid = geteuid();
198 egid = getegid();
199 while ((ch = getopt(argc, argv, "fh:p")) != -1)
200 switch (ch) {
201 case 'f':
202 fflag = 1;
203 break;
204 case 'h':
205 if (uid)
206 errx(1, "-h option: %s", strerror(EPERM));
207 hflag = 1;
208 if (strlcpy(full_hostname, optarg,
209 sizeof(full_hostname)) >= sizeof(full_hostname))
210 errx(1, "-h option: %s: exceeds maximum "
211 "hostname size", optarg);
213 trimdomain(optarg, UT_HOSTSIZE);
215 if (strlen(optarg) > UT_HOSTSIZE) {
216 struct addrinfo hints, *res;
217 int ga_err;
219 memset(&hints, 0, sizeof(hints));
220 hints.ai_family = AF_UNSPEC;
221 ga_err = getaddrinfo(optarg, NULL, &hints,
222 &res);
223 if (ga_err == 0) {
224 char hostbuf[MAXHOSTNAMELEN];
226 getnameinfo(res->ai_addr,
227 res->ai_addrlen,
228 hostbuf,
229 sizeof(hostbuf), NULL, 0,
230 NI_NUMERICHOST|
231 NI_WITHSCOPEID);
232 optarg = strdup(hostbuf);
233 if (optarg == NULL) {
234 syslog(LOG_NOTICE,
235 "strdup(): %m");
236 sleepexit(1);
238 } else
239 optarg = "invalid hostname";
240 if (res != NULL)
241 freeaddrinfo(res);
243 hostname = optarg;
244 break;
245 case 'p':
246 pflag = 1;
247 break;
248 case '?':
249 default:
250 if (!uid)
251 syslog(LOG_ERR, "invalid flag %c", ch);
252 usage();
254 argc -= optind;
255 argv += optind;
257 if (*argv) {
258 username = *argv;
259 ask = 0;
260 } else
261 ask = 1;
263 setproctitle("-%s", getprogname());
265 for (cnt = getdtablesize(); cnt > 2; cnt--)
266 (void)close(cnt);
268 ttyn = ttyname(STDIN_FILENO);
269 if (ttyn == NULL || *ttyn == '\0') {
270 (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY);
271 ttyn = tname;
273 if ((tty = strrchr(ttyn, '/')) != NULL)
274 ++tty;
275 else
276 tty = ttyn;
279 * Get "login-retries" & "login-backoff" from default class
281 lc = login_getclass(NULL);
282 prompt = login_getcapstr(lc, "login_prompt",
283 DEFAULT_PROMPT, DEFAULT_PROMPT);
284 passwd_prompt = login_getcapstr(lc, "passwd_prompt",
285 DEFAULT_PASSWD_PROMPT, DEFAULT_PASSWD_PROMPT);
286 retries = login_getcapnum(lc, "login-retries", DEFAULT_RETRIES,
287 DEFAULT_RETRIES);
288 backoff = login_getcapnum(lc, "login-backoff", DEFAULT_BACKOFF,
289 DEFAULT_BACKOFF);
290 login_close(lc);
291 lc = NULL;
293 for (cnt = 0;; ask = 1) {
294 if (ask) {
295 fflag = 0;
296 getloginname();
298 rootlogin = 0;
299 rootok = rootterm(tty); /* Default (auth may change) */
301 if (strlen(username) > UT_NAMESIZE)
302 username[UT_NAMESIZE] = '\0';
305 * Note if trying multiple user names; log failures for
306 * previous user name, but don't bother logging one failure
307 * for nonexistent name (mistyped username).
309 if (failures && strcmp(tbuf, username)) {
310 if (failures > (pwd ? 0 : 1))
311 badlogin(tbuf);
313 (void)strlcpy(tbuf, username, sizeof(tbuf));
315 pwd = getpwnam(username);
318 * if we have a valid account name, and it doesn't have a
319 * password, or the -f option was specified and the caller
320 * is root or the caller isn't changing their uid, don't
321 * authenticate.
323 if (pwd != NULL) {
324 if (pwd->pw_uid == 0)
325 rootlogin = 1;
327 if (fflag && (uid == (uid_t)0 ||
328 uid == (uid_t)pwd->pw_uid)) {
329 /* already authenticated */
330 break;
331 } else if (pwd->pw_passwd[0] == '\0') {
332 if (!rootlogin || rootok) {
333 /* pretend password okay */
334 rval = 0;
335 goto ttycheck;
340 fflag = 0;
342 (void)setpriority(PRIO_PROCESS, 0, -4);
344 #ifdef USE_PAM
346 * Try to authenticate using PAM. If a PAM system error
347 * occurs, perhaps because of a botched configuration,
348 * then fall back to using traditional Unix authentication.
350 if ((rval = auth_pam()) == -1)
351 #endif /* USE_PAM */
352 rval = auth_traditional();
354 (void)setpriority(PRIO_PROCESS, 0, 0);
356 #ifdef USE_PAM
358 * PAM authentication may have changed "pwd" to the
359 * entry for the template user. Check again to see if
360 * this is a root login after all.
362 if (pwd != NULL && pwd->pw_uid == 0)
363 rootlogin = 1;
364 #endif /* USE_PAM */
366 ttycheck:
368 * If trying to log in as root without Kerberos,
369 * but with insecure terminal, refuse the login attempt.
371 if (pwd && !rval) {
372 if (rootlogin && !rootok)
373 refused(NULL, "NOROOT", 0);
374 else /* valid password & authenticated */
375 break;
378 (void)printf("Login incorrect\n");
379 failures++;
382 * we allow up to 'retry' (10) tries,
383 * but after 'backoff' (3) we start backing off
385 if (++cnt > backoff) {
386 if (cnt >= retries) {
387 badlogin(username);
388 sleepexit(1);
390 sleep((u_int)((cnt - backoff) * 5));
394 /* committed to login -- turn off timeout */
395 (void)alarm((u_int)0);
396 (void)signal(SIGHUP, SIG_DFL);
398 endpwent();
401 * Establish the login class.
403 lc = login_getpwclass(pwd);
405 /* if user not super-user, check for disabled logins */
406 if (!rootlogin)
407 auth_checknologin(lc);
409 quietlog = login_getcapbool(lc, "hushlogin", 0);
410 /* Switching needed for NFS with root access disabled */
411 (void)setegid(pwd->pw_gid);
412 (void)seteuid(rootlogin ? 0 : pwd->pw_uid);
413 if (!*pwd->pw_dir || chdir(pwd->pw_dir) < 0) {
414 if (login_getcapbool(lc, "requirehome", 0))
415 refused("Home directory not available", "HOMEDIR", 1);
416 if (chdir("/") < 0)
417 refused("Cannot find root directory", "ROOTDIR", 1);
418 if (!quietlog || *pwd->pw_dir)
419 printf("No home directory.\nLogging in with home = \"/\".\n");
420 pwd->pw_dir = "/";
422 (void)seteuid(euid);
423 (void)setegid(egid);
424 if (!quietlog)
425 quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0;
427 if (pwd->pw_change || pwd->pw_expire)
428 (void)gettimeofday(&tp, (struct timezone *)NULL);
430 #define DEFAULT_WARN (2L * 7L * 86400L) /* Two weeks */
432 warntime = login_getcaptime(lc, "warnexpire", DEFAULT_WARN,
433 DEFAULT_WARN);
435 if (pwd->pw_expire) {
436 if (tp.tv_sec >= pwd->pw_expire) {
437 refused("Sorry -- your account has expired", "EXPIRED",
439 } else if (pwd->pw_expire - tp.tv_sec < warntime && !quietlog)
440 (void)printf("Warning: your account expires on %s",
441 ctime(&pwd->pw_expire));
444 warntime = login_getcaptime(lc, "warnpassword", DEFAULT_WARN,
445 DEFAULT_WARN);
447 changepass = 0;
448 if (pwd->pw_change) {
449 if (tp.tv_sec >= pwd->pw_change) {
450 (void)printf("Sorry -- your password has expired.\n");
451 changepass = 1;
452 syslog(LOG_INFO, "%s Password expired - forcing change",
453 pwd->pw_name);
454 } else if (pwd->pw_change - tp.tv_sec < warntime && !quietlog)
455 (void)printf("Warning: your password expires on %s",
456 ctime(&pwd->pw_change));
459 if (lc != NULL) {
460 if (hostname) {
461 struct addrinfo hints, *res;
462 int ga_err;
464 memset(&hints, 0, sizeof(hints));
465 hints.ai_family = AF_UNSPEC;
466 ga_err = getaddrinfo(full_hostname, NULL, &hints,
467 &res);
468 if (ga_err == 0) {
469 char hostbuf[MAXHOSTNAMELEN];
471 getnameinfo(res->ai_addr, res->ai_addrlen,
472 hostbuf, sizeof(hostbuf), NULL, 0,
473 NI_NUMERICHOST|NI_WITHSCOPEID);
474 if ((optarg = strdup(hostbuf)) == NULL) {
475 syslog(LOG_NOTICE, "strdup(): %m");
476 sleepexit(1);
478 } else
479 optarg = NULL;
480 if (res != NULL)
481 freeaddrinfo(res);
482 if (!auth_hostok(lc, full_hostname, optarg))
483 refused("Permission denied", "HOST", 1);
486 if (!auth_ttyok(lc, tty))
487 refused("Permission denied", "TTY", 1);
489 if (!auth_timeok(lc, time(NULL)))
490 refused("Logins not available right now", "TIME", 1);
492 shell = login_getcapstr(lc, "shell", pwd->pw_shell, pwd->pw_shell);
493 if (*pwd->pw_shell == '\0')
494 pwd->pw_shell = _PATH_BSHELL;
495 if (*shell == '\0') /* Not overridden */
496 shell = pwd->pw_shell;
497 if ((shell = strdup(shell)) == NULL) {
498 syslog(LOG_NOTICE, "strdup(): %m");
499 sleepexit(1);
502 #ifdef LOGIN_ACCESS
503 if (login_access(pwd->pw_name, hostname ? full_hostname : tty) == 0)
504 refused("Permission denied", "ACCESS", 1);
505 #endif /* LOGIN_ACCESS */
507 /* Nothing else left to fail -- really log in. */
508 memset((void *)&utmp, 0, sizeof(utmp));
509 (void)time(&utmp.ut_time);
510 (void)strncpy(utmp.ut_name, username, sizeof(utmp.ut_name));
511 if (hostname)
512 (void)strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host));
513 (void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line));
514 login(&utmp);
516 dolastlog(quietlog);
519 * Set device protections, depending on what terminal the
520 * user is logged in. This feature is used on Suns to give
521 * console users better privacy.
523 login_fbtab(tty, pwd->pw_uid, pwd->pw_gid);
526 * Clear flags of the tty. None should be set, and when the
527 * user sets them otherwise, this can cause the chown to fail.
528 * Since it isn't clear that flags are useful on character
529 * devices, we just clear them.
531 if (ttyn != tname && chflags(ttyn, 0) && errno != EOPNOTSUPP)
532 syslog(LOG_ERR, "chflags(%s): %m", ttyn);
533 if (ttyn != tname && chown(ttyn, pwd->pw_uid,
534 (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid))
535 syslog(LOG_ERR, "chmod(%s): %m", ttyn);
539 * Preserve TERM if it happens to be already set.
541 if ((term = getenv("TERM")) != NULL) {
542 if ((term = strdup(term)) == NULL) {
543 syslog(LOG_NOTICE,
544 "strdup(): %m");
545 sleepexit(1);
550 * Exclude cons/vt/ptys only, assume dialup otherwise
551 * TODO: Make dialup tty determination a library call
552 * for consistency (finger etc.)
554 if (hostname==NULL && isdialuptty(tty))
555 syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name);
557 #ifdef LOGALL
559 * Syslog each successful login, so we don't have to watch hundreds
560 * of wtmp or lastlogin files.
562 if (hostname)
563 syslog(LOG_INFO, "login from %s on %s as %s",
564 full_hostname, tty, pwd->pw_name);
565 else
566 syslog(LOG_INFO, "login on %s as %s",
567 tty, pwd->pw_name);
568 #endif
571 * If fflag is on, assume caller/authenticator has logged root login.
573 if (rootlogin && fflag == 0)
575 if (hostname)
576 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s",
577 username, tty, full_hostname);
578 else
579 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s",
580 username, tty);
584 * Destroy environment unless user has requested its preservation.
585 * We need to do this before setusercontext() because that may
586 * set or reset some environment variables.
588 if (!pflag)
589 environ = envinit;
592 * PAM modules might add supplementary groups during pam_setcred().
594 if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETGROUP) != 0) {
595 syslog(LOG_ERR, "setusercontext() failed - exiting");
596 exit(1);
599 #ifdef USE_PAM
600 if (pamh) {
601 if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
602 syslog(LOG_ERR, "pam_open_session: %s",
603 pam_strerror(pamh, e));
604 } else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED))
605 != PAM_SUCCESS) {
606 syslog(LOG_ERR, "pam_setcred: %s",
607 pam_strerror(pamh, e));
611 * Add any environmental variables that the
612 * PAM modules may have set.
613 * Call *after* opening session!
615 if (pamh) {
616 environ_pam = pam_getenvlist(pamh);
617 if (environ_pam)
618 export_pam_environment();
622 * We must fork() before setuid() because we need to call
623 * pam_close_session() as root.
625 pid = fork();
626 if (pid < 0) {
627 err(1, "fork");
628 PAM_END;
629 exit(0);
630 } else if (pid) {
631 /* parent - wait for child to finish, then cleanup
632 session */
633 setproctitle("-%s [pam]", getprogname());
634 wait(NULL);
635 PAM_END;
636 exit(0);
637 } else {
638 if ((e = pam_end(pamh, PAM_SILENT)) != PAM_SUCCESS)
639 syslog(LOG_ERR, "pam_end: %s",
640 pam_strerror(pamh, e));
643 #endif /* USE_PAM */
646 * We don't need to be root anymore, so
647 * set the user and session context
649 if (setlogin(username) != 0) {
650 syslog(LOG_ERR, "setlogin(%s): %m - exiting", username);
651 exit(1);
653 if (setusercontext(lc, pwd, pwd->pw_uid,
654 LOGIN_SETALL & ~(LOGIN_SETLOGIN|LOGIN_SETGROUP)) != 0) {
655 syslog(LOG_ERR, "setusercontext() failed - exiting");
656 exit(1);
659 if (setenv("SHELL", pwd->pw_shell, 1) == -1)
660 err(1, "setenv: cannot set SHELL=%s", pwd->pw_shell);
661 if (setenv("HOME", pwd->pw_dir, 1) == -1)
662 err(1, "setenv: cannot set HOME=%s", pwd->pw_dir);
663 if (term != NULL && *term != '\0') {
664 if (setenv("TERM", term, 1) == -1) /* Preset overrides */
665 err(1, "setenv: cannot set TERM=%s", term);
667 else {
668 if (setenv("TERM", stypeof(tty), 0) == -1) /* Fallback doesn't */
669 err(1, "setenv: cannot set TERM=%s", stypeof(tty));
671 if (setenv("LOGNAME", username, 1) == -1)
672 err(1, "setenv: cannot set LOGNAME=%s", username);
673 if (setenv("USER", username, 1) == -1)
674 err(1, "setenv: cannot set USER=%s", username);
675 if (setenv("PATH", rootlogin ? _PATH_STDPATH : _PATH_DEFPATH, 0) == -1)
676 err(1, "setenv: cannot set PATH=%s", rootlogin ? _PATH_STDPATH : _PATH_DEFPATH);
678 if (!quietlog) {
679 char *cw;
681 cw = login_getcapstr(lc, "copyright", NULL, NULL);
682 if (cw != NULL && access(cw, F_OK) == 0)
683 motd(cw);
684 else
685 (void)printf("%s\n\t%s %s\n",
686 "Copyright (c) 1980, 1983, 1986, 1988, 1990, 1991, 1993, 1994",
687 "The Regents of the University of California. ",
688 "All rights reserved.");
690 (void)printf("\n");
692 cw = login_getcapstr(lc, "welcome", NULL, NULL);
693 if (cw == NULL || access(cw, F_OK) != 0)
694 cw = _PATH_MOTDFILE;
695 motd(cw);
697 cw = getenv("MAIL"); /* $MAIL may have been set by class */
698 if (cw != NULL)
699 strlcpy(tbuf, cw, sizeof(tbuf));
700 else
701 snprintf(tbuf, sizeof(tbuf), "%s/%s", _PATH_MAILDIR,
702 pwd->pw_name);
703 if (stat(tbuf, &st) == 0 && st.st_size != 0)
704 (void)printf("You have %smail.\n",
705 (st.st_mtime > st.st_atime) ? "new " : "");
708 login_close(lc);
710 (void)signal(SIGALRM, SIG_DFL);
711 (void)signal(SIGQUIT, SIG_DFL);
712 (void)signal(SIGINT, SIG_DFL);
713 (void)signal(SIGTSTP, SIG_IGN);
715 if (changepass) {
716 if (system(_PATH_CHPASS) != 0)
717 sleepexit(1);
721 * Login shells have a leading '-' in front of argv[0]
723 if (snprintf(tbuf, sizeof(tbuf), "-%s",
724 (p = strrchr(pwd->pw_shell, '/')) ? p + 1 : pwd->pw_shell) >=
725 sizeof(tbuf)) {
726 syslog(LOG_ERR, "user: %s: shell exceeds maximum pathname size",
727 username);
728 errx(1, "shell exceeds maximum pathname size");
731 execlp(shell, tbuf, (char *)0);
732 err(1, "%s", shell);
735 static int
736 auth_traditional(void)
738 int rval;
739 char *p;
740 char *ep;
741 char *salt;
743 rval = 1;
744 salt = pwd != NULL ? pwd->pw_passwd : "xx";
746 p = getpass(passwd_prompt);
747 ep = crypt(p, salt);
749 if (pwd) {
750 if (!p[0] && pwd->pw_passwd[0])
751 ep = ":";
752 if (strcmp(ep, pwd->pw_passwd) == 0)
753 rval = 0;
756 /* clear entered password */
757 memset(p, 0, strlen(p));
758 return rval;
761 #ifdef USE_PAM
763 * Attempt to authenticate the user using PAM. Returns 0 if the user is
764 * authenticated, or 1 if not authenticated. If some sort of PAM system
765 * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
766 * function returns -1. This can be used as an indication that we should
767 * fall back to a different authentication mechanism.
769 static int
770 auth_pam(void)
772 const char *tmpl_user;
773 const void *item;
774 int rval;
775 int e;
776 static struct pam_conv conv;
778 conv.conv = &openpam_ttyconv;
780 if ((e = pam_start("login", username, &conv, &pamh)) != PAM_SUCCESS) {
781 syslog(LOG_ERR, "pam_start: %s", pam_strerror(pamh, e));
782 return -1;
784 if ((e = pam_set_item(pamh, PAM_TTY, tty)) != PAM_SUCCESS) {
785 syslog(LOG_ERR, "pam_set_item(PAM_TTY): %s",
786 pam_strerror(pamh, e));
787 return -1;
789 if (hostname != NULL &&
790 (e = pam_set_item(pamh, PAM_RHOST, full_hostname)) != PAM_SUCCESS) {
791 syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
792 pam_strerror(pamh, e));
793 return -1;
795 e = pam_authenticate(pamh, 0);
796 switch (e) {
798 case PAM_SUCCESS:
800 * With PAM we support the concept of a "template"
801 * user. The user enters a login name which is
802 * authenticated by PAM, usually via a remote service
803 * such as RADIUS or TACACS+. If authentication
804 * succeeds, a different but related "template" name
805 * is used for setting the credentials, shell, and
806 * home directory. The name the user enters need only
807 * exist on the remote authentication server, but the
808 * template name must be present in the local password
809 * database.
811 * This is supported by two various mechanisms in the
812 * individual modules. However, from the application's
813 * point of view, the template user is always passed
814 * back as a changed value of the PAM_USER item.
816 if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
817 PAM_SUCCESS) {
818 tmpl_user = (const char *) item;
819 if (strcmp(username, tmpl_user) != 0)
820 pwd = getpwnam(tmpl_user);
821 } else
822 syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
823 pam_strerror(pamh, e));
824 rval = 0;
825 break;
827 case PAM_AUTH_ERR:
828 case PAM_USER_UNKNOWN:
829 case PAM_MAXTRIES:
830 rval = 1;
831 break;
833 default:
834 syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
835 rval = -1;
836 break;
839 if (rval == 0) {
840 e = pam_acct_mgmt(pamh, 0);
841 if (e == PAM_NEW_AUTHTOK_REQD) {
842 e = pam_chauthtok(pamh, PAM_CHANGE_EXPIRED_AUTHTOK);
843 if (e != PAM_SUCCESS) {
844 syslog(LOG_ERR, "pam_chauthtok: %s",
845 pam_strerror(pamh, e));
846 rval = 1;
848 } else if (e != PAM_SUCCESS) {
849 rval = 1;
853 if (rval != 0) {
854 if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
855 syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
857 pamh = NULL;
859 return rval;
862 static int
863 export_pam_environment(void)
865 char **pp;
867 for (pp = environ_pam; *pp != NULL; pp++) {
868 if (ok_to_export(*pp)) {
869 if (putenv(*pp) == -1)
870 err(1, "putenv: cannot set %s", *pp);
872 free(*pp);
874 return PAM_SUCCESS;
878 * Sanity checks on PAM environmental variables:
879 * - Make sure there is an '=' in the string.
880 * - Make sure the string doesn't run on too long.
881 * - Do not export certain variables. This list was taken from the
882 * Solaris pam_putenv(3) man page.
884 static int
885 ok_to_export(const char *s)
887 static const char *noexport[] = {
888 "SHELL", "HOME", "LOGNAME", "MAIL", "CDPATH",
889 "IFS", "PATH", NULL
891 const char **pp;
892 size_t n;
894 if (strlen(s) > 1024 || strchr(s, '=') == NULL)
895 return 0;
896 if (strncmp(s, "LD_", 3) == 0)
897 return 0;
898 for (pp = noexport; *pp != NULL; pp++) {
899 n = strlen(*pp);
900 if (s[n] == '=' && strncmp(s, *pp, n) == 0)
901 return 0;
903 return 1;
905 #endif /* USE_PAM */
907 static void
908 usage(void)
911 (void)fprintf(stderr, "usage: login [-fp] [-h hostname] [username]\n");
912 exit(1);
916 * Allow for authentication style and/or kerberos instance
919 #define NBUFSIZ UT_NAMESIZE + 64
921 void
922 getloginname(void)
924 int ch;
925 char *p;
926 static char nbuf[NBUFSIZ];
928 for (;;) {
929 (void)printf("%s", prompt);
930 for (p = nbuf; (ch = getchar()) != '\n'; ) {
931 if (ch == EOF) {
932 badlogin(username);
933 exit(0);
935 if (p < nbuf + (NBUFSIZ - 1))
936 *p++ = ch;
938 if (p > nbuf) {
939 if (nbuf[0] == '-')
940 (void)fprintf(stderr,
941 "login names may not start with '-'.\n");
942 else {
943 *p = '\0';
944 username = nbuf;
945 break;
952 rootterm(char *ttyn)
954 struct ttyent *t;
956 return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE);
959 volatile int motdinterrupt;
961 void
962 sigint(int signo __unused)
964 motdinterrupt = 1;
967 void
968 motd(char *motdfile)
970 int fd, nchars;
971 sig_t oldint;
972 char tbuf[256];
974 if ((fd = open(motdfile, O_RDONLY, 0)) < 0)
975 return;
976 motdinterrupt = 0;
977 oldint = signal(SIGINT, sigint);
978 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0 && !motdinterrupt)
979 (void)write(fileno(stdout), tbuf, nchars);
980 (void)signal(SIGINT, oldint);
981 (void)close(fd);
984 /* ARGSUSED */
985 void
986 timedout(int signo)
989 longjmp(timeout_buf, signo);
993 void
994 dolastlog(int quiet)
996 struct lastlog ll;
997 int fd;
999 if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) >= 0) {
1000 (void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), L_SET);
1001 if (!quiet) {
1002 if (read(fd, (char *)&ll, sizeof(ll)) == sizeof(ll) &&
1003 ll.ll_time != 0) {
1004 (void)printf("Last login: %.*s ",
1005 24-5, (char *)ctime(&ll.ll_time));
1006 if (*ll.ll_host != '\0')
1007 (void)printf("from %.*s\n",
1008 (int)sizeof(ll.ll_host),
1009 ll.ll_host);
1010 else
1011 (void)printf("on %.*s\n",
1012 (int)sizeof(ll.ll_line),
1013 ll.ll_line);
1015 (void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), L_SET);
1017 memset((void *)&ll, 0, sizeof(ll));
1018 (void)time(&ll.ll_time);
1019 (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line));
1020 if (hostname)
1021 (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host));
1022 (void)write(fd, (char *)&ll, sizeof(ll));
1023 (void)close(fd);
1024 } else {
1025 syslog(LOG_ERR, "cannot open %s: %m", _PATH_LASTLOG);
1029 void
1030 badlogin(char *name)
1033 if (failures == 0)
1034 return;
1035 if (hostname) {
1036 syslog(LOG_NOTICE, "%d LOGIN FAILURE%s FROM %s",
1037 failures, failures > 1 ? "S" : "", full_hostname);
1038 syslog(LOG_AUTHPRIV|LOG_NOTICE,
1039 "%d LOGIN FAILURE%s FROM %s, %s",
1040 failures, failures > 1 ? "S" : "", full_hostname, name);
1041 } else {
1042 syslog(LOG_NOTICE, "%d LOGIN FAILURE%s ON %s",
1043 failures, failures > 1 ? "S" : "", tty);
1044 syslog(LOG_AUTHPRIV|LOG_NOTICE,
1045 "%d LOGIN FAILURE%s ON %s, %s",
1046 failures, failures > 1 ? "S" : "", tty, name);
1048 failures = 0;
1051 #undef UNKNOWN
1052 #define UNKNOWN "su"
1054 char *
1055 stypeof(char *ttyid)
1057 struct ttyent *t;
1059 if (ttyid != NULL && *ttyid != '\0') {
1060 t = getttynam(ttyid);
1061 if (t != NULL && t->ty_type != NULL)
1062 return (t->ty_type);
1064 return (UNKNOWN);
1067 void
1068 refused(char *msg, char *rtype, int lout)
1071 if (msg != NULL)
1072 printf("%s.\n", msg);
1073 if (hostname)
1074 syslog(LOG_NOTICE, "LOGIN %s REFUSED (%s) FROM %s ON TTY %s",
1075 pwd->pw_name, rtype, full_hostname, tty);
1076 else
1077 syslog(LOG_NOTICE, "LOGIN %s REFUSED (%s) ON TTY %s",
1078 pwd->pw_name, rtype, tty);
1079 if (lout)
1080 sleepexit(1);
1083 void
1084 sleepexit(int eval)
1087 (void)sleep(5);
1088 exit(eval);