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login_pam.c revision 1.8
      1  1.8      matt /*     $NetBSD: login_pam.c,v 1.8 2005/04/25 01:34:38 matt Exp $       */
      2  1.1      manu 
      3  1.1      manu /*-
      4  1.1      manu  * Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994
      5  1.1      manu  *	The Regents of the University of California.  All rights reserved.
      6  1.1      manu  *
      7  1.1      manu  * Redistribution and use in source and binary forms, with or without
      8  1.1      manu  * modification, are permitted provided that the following conditions
      9  1.1      manu  * are met:
     10  1.1      manu  * 1. Redistributions of source code must retain the above copyright
     11  1.1      manu  *    notice, this list of conditions and the following disclaimer.
     12  1.1      manu  * 2. Redistributions in binary form must reproduce the above copyright
     13  1.1      manu  *    notice, this list of conditions and the following disclaimer in the
     14  1.1      manu  *    documentation and/or other materials provided with the distribution.
     15  1.1      manu  * 3. Neither the name of the University nor the names of its contributors
     16  1.1      manu  *    may be used to endorse or promote products derived from this software
     17  1.1      manu  *    without specific prior written permission.
     18  1.1      manu  *
     19  1.1      manu  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  1.1      manu  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  1.1      manu  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  1.1      manu  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  1.1      manu  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  1.1      manu  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  1.1      manu  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  1.1      manu  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  1.1      manu  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  1.1      manu  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  1.1      manu  * SUCH DAMAGE.
     30  1.1      manu  */
     31  1.1      manu 
     32  1.1      manu #include <sys/cdefs.h>
     33  1.1      manu #ifndef lint
     34  1.1      manu __COPYRIGHT(
     35  1.1      manu "@(#) Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994\n\
     36  1.1      manu 	The Regents of the University of California.  All rights reserved.\n");
     37  1.1      manu #endif /* not lint */
     38  1.1      manu 
     39  1.1      manu #ifndef lint
     40  1.1      manu #if 0
     41  1.1      manu static char sccsid[] = "@(#)login.c	8.4 (Berkeley) 4/2/94";
     42  1.1      manu #endif
     43  1.8      matt __RCSID("$NetBSD: login_pam.c,v 1.8 2005/04/25 01:34:38 matt Exp $");
     44  1.1      manu #endif /* not lint */
     45  1.1      manu 
     46  1.1      manu /*
     47  1.1      manu  * login [ name ]
     48  1.1      manu  * login -h hostname	(for telnetd, etc.)
     49  1.1      manu  * login -f name	(for pre-authenticated login: datakit, xterm, etc.)
     50  1.1      manu  */
     51  1.1      manu 
     52  1.1      manu #include <sys/param.h>
     53  1.1      manu #include <sys/stat.h>
     54  1.1      manu #include <sys/time.h>
     55  1.1      manu #include <sys/resource.h>
     56  1.1      manu #include <sys/file.h>
     57  1.1      manu #include <sys/wait.h>
     58  1.1      manu #include <sys/socket.h>
     59  1.1      manu 
     60  1.1      manu #include <err.h>
     61  1.1      manu #include <errno.h>
     62  1.1      manu #include <grp.h>
     63  1.1      manu #include <pwd.h>
     64  1.1      manu #include <setjmp.h>
     65  1.1      manu #include <signal.h>
     66  1.1      manu #include <stdio.h>
     67  1.1      manu #include <stdlib.h>
     68  1.1      manu #include <string.h>
     69  1.1      manu #include <syslog.h>
     70  1.1      manu #include <time.h>
     71  1.1      manu #include <ttyent.h>
     72  1.1      manu #include <tzfile.h>
     73  1.1      manu #include <unistd.h>
     74  1.1      manu #include <util.h>
     75  1.1      manu #include <login_cap.h>
     76  1.1      manu #include <vis.h>
     77  1.1      manu 
     78  1.1      manu #include <security/pam_appl.h>
     79  1.1      manu #include <security/openpam.h>
     80  1.1      manu 
     81  1.1      manu #include "pathnames.h"
     82  1.1      manu 
     83  1.1      manu void	 badlogin (char *);
     84  1.1      manu static void	 update_db (int);
     85  1.1      manu void	 getloginname (void);
     86  1.1      manu int	 main (int, char *[]);
     87  1.1      manu void	 motd (char *);
     88  1.1      manu int	 rootterm (char *);
     89  1.1      manu void	 sigint (int);
     90  1.1      manu void	 sleepexit (int);
     91  1.1      manu const	 char *stypeof (const char *);
     92  1.1      manu void	 timedout (int);
     93  1.1      manu void	 decode_ss (const char *);
     94  1.1      manu void	 usage (void);
     95  1.1      manu 
     96  1.1      manu static struct pam_conv pamc = { openpam_ttyconv, NULL };
     97  1.1      manu 
     98  1.1      manu #define	TTYGRPNAME	"tty"		/* name of group to own ttys */
     99  1.1      manu 
    100  1.1      manu #define DEFAULT_BACKOFF 3
    101  1.1      manu #define DEFAULT_RETRIES 10
    102  1.1      manu 
    103  1.1      manu /*
    104  1.1      manu  * This bounds the time given to login.  Not a define so it can
    105  1.1      manu  * be patched on machines where it's too small.
    106  1.1      manu  */
    107  1.1      manu u_int	timeout = 300;
    108  1.1      manu 
    109  1.5  christos struct	passwd *pwd, pwres;
    110  1.5  christos char	pwbuf[1024];
    111  1.3  christos struct	group *gr;
    112  1.1      manu int	failures, have_ss;
    113  1.1      manu char	term[64], *envinit[1], *hostname, *username, *tty, *nested;
    114  1.1      manu struct timeval now;
    115  1.1      manu struct sockaddr_storage ss;
    116  1.1      manu 
    117  1.1      manu extern const char copyrightstr[];
    118  1.1      manu 
    119  1.1      manu int
    120  1.1      manu main(int argc, char *argv[])
    121  1.1      manu {
    122  1.1      manu 	extern char **environ;
    123  1.1      manu 	struct stat st;
    124  1.1      manu 	int ask, ch, cnt, fflag, hflag, pflag, sflag, quietlog, rootlogin;
    125  1.1      manu 	int auth_passed;
    126  1.1      manu 	int Fflag;
    127  1.1      manu 	uid_t uid, saved_uid;
    128  1.1      manu 	gid_t saved_gid, saved_gids[NGROUPS_MAX];
    129  1.1      manu 	int nsaved_gids;
    130  1.1      manu 	char *domain, *p, *ttyn, *pwprompt;
    131  1.1      manu 	char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10];
    132  1.1      manu 	char localhost[MAXHOSTNAMELEN + 1];
    133  1.1      manu 	int need_chpass, require_chpass;
    134  1.1      manu 	int login_retries = DEFAULT_RETRIES,
    135  1.1      manu 	    login_backoff = DEFAULT_BACKOFF;
    136  1.1      manu 	char *shell = NULL;
    137  1.1      manu 	login_cap_t *lc = NULL;
    138  1.1      manu 	pam_handle_t *pamh = NULL;
    139  1.1      manu 	int pam_err;
    140  1.1      manu 	void *oint;
    141  1.1      manu 	void *oabrt;
    142  1.1      manu 	const void *newuser;
    143  1.1      manu 	int pam_silent = PAM_SILENT;
    144  1.1      manu 	pid_t xpid, pid;
    145  1.1      manu 	int status;
    146  1.1      manu 	char *saved_term;
    147  1.1      manu 	char **pamenv;
    148  1.1      manu 
    149  1.1      manu 	tbuf[0] = '\0';
    150  1.1      manu 	pwprompt = NULL;
    151  1.1      manu 	nested = NULL;
    152  1.1      manu 	need_chpass = require_chpass = 0;
    153  1.1      manu 
    154  1.1      manu 	(void)signal(SIGALRM, timedout);
    155  1.1      manu 	(void)alarm(timeout);
    156  1.1      manu 	(void)signal(SIGQUIT, SIG_IGN);
    157  1.1      manu 	(void)signal(SIGINT, SIG_IGN);
    158  1.1      manu 	(void)setpriority(PRIO_PROCESS, 0, 0);
    159  1.1      manu 
    160  1.1      manu 	openlog("login", 0, LOG_AUTH);
    161  1.1      manu 
    162  1.1      manu 	/*
    163  1.1      manu 	 * -p is used by getty to tell login not to destroy the environment
    164  1.1      manu 	 * -f is used to skip a second login authentication
    165  1.1      manu 	 * -h is used by other servers to pass the name of the remote host to
    166  1.1      manu 	 *    login so that it may be placed in utmp/utmpx and wtmp/wtmpx
    167  1.1      manu 	 * -a in addition to -h, a server my supply -a to pass the actual
    168  1.1      manu 	 *    server address.
    169  1.1      manu 	 * -s is used to force use of S/Key or equivalent.
    170  1.1      manu 	 */
    171  1.1      manu 	domain = NULL;
    172  1.1      manu 	if (gethostname(localhost, sizeof(localhost)) < 0)
    173  1.1      manu 		syslog(LOG_ERR, "couldn't get local hostname: %m");
    174  1.1      manu 	else
    175  1.1      manu 		domain = strchr(localhost, '.');
    176  1.1      manu 	localhost[sizeof(localhost) - 1] = '\0';
    177  1.1      manu 
    178  1.1      manu 	Fflag = fflag = hflag = pflag = sflag = 0;
    179  1.1      manu 	have_ss = 0;
    180  1.1      manu 	uid = getuid();
    181  1.1      manu 	while ((ch = getopt(argc, argv, "a:Ffh:ps")) != -1)
    182  1.1      manu 		switch (ch) {
    183  1.1      manu 		case 'a':
    184  1.5  christos 			if (uid) {
    185  1.5  christos 				errno = EPERM;
    186  1.5  christos 				err(EXIT_FAILURE, "-a option");
    187  1.5  christos 			}
    188  1.1      manu 			decode_ss(optarg);
    189  1.3  christos #ifdef notdef
    190  1.3  christos 			(void)sockaddr_snprintf(optarg,
    191  1.3  christos 			    sizeof(struct sockaddr_storage), "%a", (void *)&ss);
    192  1.3  christos #endif
    193  1.1      manu 			break;
    194  1.1      manu 		case 'F':
    195  1.1      manu 			Fflag = 1;
    196  1.1      manu 			/* FALLTHROUGH */
    197  1.1      manu 		case 'f':
    198  1.1      manu 			fflag = 1;
    199  1.1      manu 			break;
    200  1.1      manu 		case 'h':
    201  1.5  christos 			if (uid) {
    202  1.5  christos 				errno = EPERM;
    203  1.5  christos 				err(EXIT_FAILURE, "-h option");
    204  1.5  christos 			}
    205  1.1      manu 			hflag = 1;
    206  1.1      manu 			if (domain && (p = strchr(optarg, '.')) != NULL &&
    207  1.1      manu 			    strcasecmp(p, domain) == 0)
    208  1.1      manu 				*p = '\0';
    209  1.1      manu 			hostname = optarg;
    210  1.1      manu 			break;
    211  1.1      manu 		case 'p':
    212  1.1      manu 			pflag = 1;
    213  1.1      manu 			break;
    214  1.1      manu 		case 's':
    215  1.1      manu 			sflag = 1;
    216  1.1      manu 			break;
    217  1.1      manu 		default:
    218  1.1      manu 		case '?':
    219  1.1      manu 			usage();
    220  1.1      manu 			break;
    221  1.1      manu 		}
    222  1.3  christos 
    223  1.3  christos 	setproctitle(NULL);
    224  1.1      manu 	argc -= optind;
    225  1.1      manu 	argv += optind;
    226  1.1      manu 
    227  1.1      manu 	if (*argv) {
    228  1.1      manu 		username = *argv;
    229  1.1      manu 		ask = 0;
    230  1.1      manu 	} else
    231  1.1      manu 		ask = 1;
    232  1.1      manu 
    233  1.3  christos #ifdef F_CLOSEM
    234  1.3  christos 	(void)fcntl(3, F_CLOSEM, 0);
    235  1.3  christos #else
    236  1.1      manu 	for (cnt = getdtablesize(); cnt > 2; cnt--)
    237  1.1      manu 		(void)close(cnt);
    238  1.3  christos #endif
    239  1.1      manu 
    240  1.1      manu 	ttyn = ttyname(STDIN_FILENO);
    241  1.1      manu 	if (ttyn == NULL || *ttyn == '\0') {
    242  1.1      manu 		(void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY);
    243  1.1      manu 		ttyn = tname;
    244  1.1      manu 	}
    245  1.3  christos 	if ((tty = strstr(ttyn, "/pts/")) != NULL)
    246  1.3  christos 		++tty;
    247  1.3  christos 	else if ((tty = strrchr(ttyn, '/')) != NULL)
    248  1.1      manu 		++tty;
    249  1.1      manu 	else
    250  1.1      manu 		tty = ttyn;
    251  1.1      manu 
    252  1.1      manu 	if (issetugid()) {
    253  1.1      manu 		nested = strdup(user_from_uid(getuid(), 0));
    254  1.1      manu 		if (nested == NULL) {
    255  1.1      manu                 	syslog(LOG_ERR, "strdup: %m");
    256  1.5  christos                 	sleepexit(EXIT_FAILURE);
    257  1.1      manu 		}
    258  1.1      manu 	}
    259  1.1      manu 
    260  1.1      manu 	/* Get "login-retries" and "login-backoff" from default class */
    261  1.1      manu 	if ((lc = login_getclass(NULL)) != NULL) {
    262  1.1      manu 		login_retries = (int)login_getcapnum(lc, "login-retries",
    263  1.1      manu 		    DEFAULT_RETRIES, DEFAULT_RETRIES);
    264  1.1      manu 		login_backoff = (int)login_getcapnum(lc, "login-backoff",
    265  1.1      manu 		    DEFAULT_BACKOFF, DEFAULT_BACKOFF);
    266  1.1      manu 		login_close(lc);
    267  1.1      manu 		lc = NULL;
    268  1.1      manu 	}
    269  1.1      manu 
    270  1.1      manu 
    271  1.1      manu 	for (cnt = 0;; ask = 1) {
    272  1.1      manu 		if (ask) {
    273  1.1      manu 			fflag = 0;
    274  1.1      manu 			getloginname();
    275  1.1      manu 		}
    276  1.1      manu 		rootlogin = 0;
    277  1.1      manu 		auth_passed = 0;
    278  1.1      manu 		if (strlen(username) > MAXLOGNAME)
    279  1.1      manu 			username[MAXLOGNAME] = '\0';
    280  1.1      manu 
    281  1.1      manu 		/*
    282  1.1      manu 		 * Note if trying multiple user names; log failures for
    283  1.1      manu 		 * previous user name, but don't bother logging one failure
    284  1.1      manu 		 * for nonexistent name (mistyped username).
    285  1.1      manu 		 */
    286  1.1      manu 		if (failures && strcmp(tbuf, username)) {
    287  1.1      manu 			if (failures > (pwd ? 0 : 1))
    288  1.1      manu 				badlogin(tbuf);
    289  1.1      manu 			failures = 0;
    290  1.1      manu 		}
    291  1.1      manu 
    292  1.1      manu #define PAM_END(msg) do { 						\
    293  1.1      manu 	syslog(LOG_ERR, "%s: %s", msg, pam_strerror(pamh, pam_err)); 	\
    294  1.1      manu 	warnx("%s: %s", msg, pam_strerror(pamh, pam_err));		\
    295  1.1      manu 	pam_end(pamh, pam_err);						\
    296  1.5  christos 	sleepexit(EXIT_FAILURE);					\
    297  1.1      manu } while (/*CONSTCOND*/0)
    298  1.1      manu 
    299  1.1      manu 		pam_err = pam_start("login", username, &pamc, &pamh);
    300  1.1      manu 		if (pam_err != PAM_SUCCESS) {
    301  1.1      manu 			if (pamh != NULL)
    302  1.1      manu 				PAM_END("pam_start");
    303  1.1      manu 			/* Things went really bad... */
    304  1.1      manu 			syslog(LOG_ERR, "pam_start failed: %s",
    305  1.1      manu 			    pam_strerror(pamh, pam_err));
    306  1.5  christos 			errx(EXIT_FAILURE, "pam_start failed");
    307  1.1      manu 		}
    308  1.1      manu 
    309  1.1      manu #define PAM_SET_ITEM(item, var)	do {					\
    310  1.1      manu 	pam_err = pam_set_item(pamh, (item), (var));			\
    311  1.1      manu 	if (pam_err != PAM_SUCCESS)					\
    312  1.1      manu 		PAM_END("pam_set_item(" # item ")");			\
    313  1.1      manu } while (/*CONSTCOND*/0)
    314  1.1      manu 
    315  1.1      manu 		/*
    316  1.4  christos 		 * Fill hostname tty, and nested user
    317  1.1      manu 		 */
    318  1.1      manu 		PAM_SET_ITEM(PAM_RHOST, hostname);
    319  1.1      manu 		PAM_SET_ITEM(PAM_TTY, tty);
    320  1.4  christos 		if (nested)
    321  1.4  christos 			PAM_SET_ITEM(PAM_NUSER, nested);
    322  1.2  christos 		if (have_ss)
    323  1.2  christos 			PAM_SET_ITEM(PAM_SOCKADDR, &ss);
    324  1.1      manu 
    325  1.6  christos 		/*
    326  1.6  christos 		 * Don't check for errors, because we don't want to give
    327  1.6  christos 		 * out any information.
    328  1.6  christos 		 */
    329  1.7     lukem 		pwd = NULL;
    330  1.6  christos 		(void)getpwnam_r(username, &pwres, pwbuf, sizeof(pwbuf), &pwd);
    331  1.1      manu 
    332  1.1      manu 		/*
    333  1.1      manu 		 * Establish the class now, before we might goto
    334  1.1      manu 		 * within the next block. pwd can be NULL since it
    335  1.1      manu 		 * falls back to the "default" class if it is.
    336  1.1      manu 		 */
    337  1.1      manu 		lc = login_getclass(pwd ? pwd->pw_class : NULL);
    338  1.1      manu 
    339  1.1      manu 		/*
    340  1.1      manu 		 * if we have a valid account name, and it doesn't have a
    341  1.1      manu 		 * password, or the -f option was specified and the caller
    342  1.1      manu 		 * is root or the caller isn't changing their uid, don't
    343  1.1      manu 		 * authenticate.
    344  1.1      manu 		 */
    345  1.1      manu 		if (pwd) {
    346  1.1      manu 			if (pwd->pw_uid == 0)
    347  1.1      manu 				rootlogin = 1;
    348  1.1      manu 
    349  1.1      manu 			if (fflag && (uid == 0 || uid == pwd->pw_uid)) {
    350  1.1      manu 				/* already authenticated */
    351  1.1      manu 				auth_passed = 1;
    352  1.1      manu 				goto skip_auth;
    353  1.1      manu 			}
    354  1.1      manu 		}
    355  1.1      manu 
    356  1.1      manu 		(void)setpriority(PRIO_PROCESS, 0, -4);
    357  1.1      manu 
    358  1.1      manu 		switch(pam_err = pam_authenticate(pamh, pam_silent)) {
    359  1.1      manu 		case PAM_SUCCESS:
    360  1.1      manu 			/*
    361  1.1      manu 			 * PAM can change the user, refresh
    362  1.1      manu 			 * username, pwd, and lc.
    363  1.1      manu 			 */
    364  1.1      manu 			pam_err = pam_get_item(pamh, PAM_USER, &newuser);
    365  1.1      manu 			if (pam_err != PAM_SUCCESS)
    366  1.1      manu 				PAM_END("pam_get_item(PAM_USER)");
    367  1.1      manu 
    368  1.1      manu 			username = (char *)newuser;
    369  1.6  christos 			/*
    370  1.6  christos 			 * Don't check for errors, because we don't want to give
    371  1.6  christos 			 * out any information.
    372  1.6  christos 			 */
    373  1.7     lukem 			pwd = NULL;
    374  1.6  christos 			(void)getpwnam_r(username, &pwres, pwbuf, sizeof(pwbuf),
    375  1.6  christos 			    &pwd);
    376  1.1      manu 			lc = login_getpwclass(pwd);
    377  1.1      manu 			auth_passed = 1;
    378  1.1      manu 
    379  1.1      manu 			switch (pam_err = pam_acct_mgmt(pamh, pam_silent)) {
    380  1.1      manu 			case PAM_SUCCESS:
    381  1.1      manu 				break;
    382  1.1      manu 
    383  1.1      manu 			case PAM_NEW_AUTHTOK_REQD:
    384  1.1      manu 				pam_err = pam_chauthtok(pamh,
    385  1.1      manu 				    pam_silent|PAM_CHANGE_EXPIRED_AUTHTOK);
    386  1.1      manu 
    387  1.1      manu 				if (pam_err != PAM_SUCCESS)
    388  1.1      manu 					PAM_END("pam_chauthtok");
    389  1.1      manu 				break;
    390  1.1      manu 
    391  1.1      manu 			default:
    392  1.1      manu 				PAM_END("pam_acct_mgmt");
    393  1.1      manu 				break;
    394  1.1      manu 			}
    395  1.1      manu 			break;
    396  1.1      manu 
    397  1.1      manu 		case PAM_AUTH_ERR:
    398  1.1      manu 		case PAM_USER_UNKNOWN:
    399  1.1      manu 		case PAM_MAXTRIES:
    400  1.1      manu 			auth_passed = 0;
    401  1.1      manu 			break;
    402  1.1      manu 
    403  1.1      manu 		default:
    404  1.1      manu 			PAM_END("pam_authenticate");
    405  1.1      manu 			break;
    406  1.1      manu 		}
    407  1.1      manu 
    408  1.1      manu 		(void)setpriority(PRIO_PROCESS, 0, 0);
    409  1.1      manu 
    410  1.1      manu skip_auth:
    411  1.1      manu 		/*
    412  1.1      manu 		 * If the user exists and authentication passed,
    413  1.1      manu 		 * get out of the loop and login the user.
    414  1.1      manu 		 */
    415  1.1      manu 		if (pwd && auth_passed)
    416  1.1      manu 			break;
    417  1.1      manu 
    418  1.1      manu 		(void)printf("Login incorrect\n");
    419  1.1      manu 		failures++;
    420  1.1      manu 		cnt++;
    421  1.1      manu 		/* we allow 10 tries, but after 3 we start backing off */
    422  1.1      manu 		if (cnt > login_backoff) {
    423  1.1      manu 			if (cnt >= login_retries) {
    424  1.1      manu 				badlogin(username);
    425  1.1      manu 				pam_end(pamh, PAM_SUCCESS);
    426  1.5  christos 				sleepexit(EXIT_FAILURE);
    427  1.1      manu 			}
    428  1.1      manu 			sleep((u_int)((cnt - 3) * 5));
    429  1.1      manu 		}
    430  1.1      manu 	}
    431  1.1      manu 
    432  1.1      manu 	/* committed to login -- turn off timeout */
    433  1.1      manu 	(void)alarm((u_int)0);
    434  1.1      manu 
    435  1.1      manu 	endpwent();
    436  1.1      manu 
    437  1.1      manu         quietlog = login_getcapbool(lc, "hushlogin", 0);
    438  1.1      manu 
    439  1.1      manu 	/*
    440  1.1      manu 	 * Temporarily give up special privileges so we can change
    441  1.1      manu 	 * into NFS-mounted homes that are exported for non-root
    442  1.1      manu 	 * access and have mode 7x0
    443  1.1      manu 	 */
    444  1.1      manu 	saved_uid = geteuid();
    445  1.1      manu 	saved_gid = getegid();
    446  1.1      manu 	nsaved_gids = getgroups(NGROUPS_MAX, saved_gids);
    447  1.1      manu 
    448  1.1      manu 	(void)setegid(pwd->pw_gid);
    449  1.1      manu 	initgroups(username, pwd->pw_gid);
    450  1.1      manu 	(void)seteuid(pwd->pw_uid);
    451  1.1      manu 
    452  1.1      manu 	if (chdir(pwd->pw_dir) != 0) {
    453  1.1      manu                 if (login_getcapbool(lc, "requirehome", 0)) {
    454  1.1      manu 			(void)printf("Home directory %s required\n",
    455  1.1      manu 			    pwd->pw_dir);
    456  1.1      manu 			pam_end(pamh, PAM_SUCCESS);
    457  1.5  christos                         exit(EXIT_FAILURE);
    458  1.1      manu 		}
    459  1.1      manu 
    460  1.1      manu 		(void)printf("No home directory %s!\n", pwd->pw_dir);
    461  1.1      manu 		if (chdir("/")) {
    462  1.1      manu 			pam_end(pamh, PAM_SUCCESS);
    463  1.5  christos 			exit(EXIT_SUCCESS);
    464  1.1      manu 		}
    465  1.1      manu 		pwd->pw_dir = "/";
    466  1.1      manu 		(void)printf("Logging in with home = \"/\".\n");
    467  1.1      manu 	}
    468  1.1      manu 
    469  1.1      manu 	if (!quietlog) {
    470  1.1      manu 		quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0;
    471  1.1      manu 		pam_silent = 0;
    472  1.1      manu 	}
    473  1.1      manu 
    474  1.1      manu 	/* regain special privileges */
    475  1.1      manu 	setegid(saved_gid);
    476  1.1      manu 	setgroups(nsaved_gids, saved_gids);
    477  1.1      manu 	seteuid(saved_uid);
    478  1.1      manu 
    479  1.3  christos 	(void)chown(ttyn, pwd->pw_uid,
    480  1.3  christos 	    (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid);
    481  1.3  christos 
    482  1.4  christos 	if (ttyaction(ttyn, "login", pwd->pw_name))
    483  1.4  christos 		(void)printf("Warning: ttyaction failed.\n");
    484  1.4  christos 
    485  1.1      manu 	/* Nothing else left to fail -- really log in. */
    486  1.1      manu         update_db(quietlog);
    487  1.1      manu 
    488  1.1      manu 	if (nested == NULL && setusercontext(lc, pwd, pwd->pw_uid,
    489  1.1      manu 	    LOGIN_SETLOGIN) != 0) {
    490  1.1      manu 		syslog(LOG_ERR, "setusercontext failed");
    491  1.1      manu 		pam_end(pamh, PAM_SUCCESS);
    492  1.5  christos 		exit(EXIT_FAILURE);
    493  1.1      manu 	}
    494  1.1      manu 
    495  1.1      manu 	if (tty[sizeof("tty")-1] == 'd')
    496  1.1      manu 		syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name);
    497  1.1      manu 
    498  1.1      manu 	/* If fflag is on, assume caller/authenticator has logged root login. */
    499  1.1      manu 	if (rootlogin && fflag == 0) {
    500  1.1      manu 		if (hostname)
    501  1.1      manu 			syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s",
    502  1.1      manu 			    username, tty, hostname);
    503  1.1      manu 		else
    504  1.1      manu 			syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s",
    505  1.1      manu 			    username, tty);
    506  1.1      manu 	}
    507  1.1      manu 
    508  1.1      manu 	/*
    509  1.1      manu 	 * Establish groups
    510  1.1      manu 	 */
    511  1.1      manu 	if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETGROUP) != 0) {
    512  1.1      manu 		syslog(LOG_ERR, "setusercontext failed");
    513  1.1      manu 		pam_end(pamh, PAM_SUCCESS);
    514  1.5  christos 		exit(EXIT_FAILURE);
    515  1.1      manu 	}
    516  1.1      manu 
    517  1.1      manu 	pam_err = pam_setcred(pamh, pam_silent|PAM_ESTABLISH_CRED);
    518  1.1      manu 	if (pam_err != PAM_SUCCESS)
    519  1.1      manu 		PAM_END("pam_setcred");
    520  1.1      manu 
    521  1.1      manu 	pam_err = pam_open_session(pamh, pam_silent);
    522  1.1      manu 	if (pam_err != PAM_SUCCESS)
    523  1.1      manu 		PAM_END("pam_open_session");
    524  1.1      manu 
    525  1.1      manu 	/*
    526  1.1      manu 	 * Fork because we need to call pam_closesession as root.
    527  1.1      manu 	 * Make sure signals cannot kill the parent.
    528  1.1      manu 	 * This is copied from crontab(8), which has to
    529  1.1      manu          * cope with a similar situation.
    530  1.1      manu 	 */
    531  1.1      manu 	oint = signal(SIGINT, SIG_IGN);
    532  1.1      manu 	oabrt = signal(SIGABRT, SIG_IGN);
    533  1.1      manu 
    534  1.1      manu 	switch(pid = fork()) {
    535  1.1      manu 	case -1:
    536  1.1      manu 		pam_err = pam_close_session(pamh, 0);
    537  1.1      manu 		if (pam_err != PAM_SUCCESS) {
    538  1.1      manu 			syslog(LOG_ERR, "pam_close_session: %s",
    539  1.1      manu 			    pam_strerror(pamh, pam_err));
    540  1.1      manu 			warnx("pam_close_session: %s",
    541  1.1      manu 			    pam_strerror(pamh, pam_err));
    542  1.1      manu 		}
    543  1.1      manu 		syslog(LOG_ERR, "fork failed: %m");
    544  1.1      manu 		warn("fork failed");
    545  1.1      manu 		pam_end(pamh, pam_err);
    546  1.5  christos 		exit(EXIT_FAILURE);
    547  1.1      manu 		break;
    548  1.1      manu 
    549  1.1      manu 	case 0: /* Child */
    550  1.1      manu 		break;
    551  1.1      manu 
    552  1.1      manu 	default:
    553  1.1      manu 		/*
    554  1.1      manu 		 * Parent: wait for the child to terminate
    555  1.1      manu 		 * and call pam_close_session.
    556  1.1      manu 		 */
    557  1.3  christos 		if ((xpid = waitpid(pid, &status, 0)) != pid) {
    558  1.1      manu 			pam_err = pam_close_session(pamh, 0);
    559  1.1      manu 			if (pam_err != PAM_SUCCESS) {
    560  1.1      manu 				syslog(LOG_ERR,
    561  1.1      manu 				    "pam_close_session: %s",
    562  1.1      manu 				    pam_strerror(pamh, pam_err));
    563  1.1      manu 				warnx("pam_close_session: %s",
    564  1.1      manu 				    pam_strerror(pamh, pam_err));
    565  1.1      manu 			}
    566  1.1      manu 			pam_end(pamh, pam_err);
    567  1.3  christos 			if (xpid != -1)
    568  1.3  christos 				warnx("wrong PID: %d != %d", pid, xpid);
    569  1.3  christos 			else
    570  1.3  christos 				warn("wait for pid %d failed", pid);
    571  1.5  christos 			exit(EXIT_FAILURE);
    572  1.1      manu 		}
    573  1.1      manu 
    574  1.1      manu 		(void)signal(SIGINT, oint);
    575  1.1      manu 		(void)signal(SIGABRT, oabrt);
    576  1.1      manu 		if ((pam_err = pam_close_session(pamh, 0)) != PAM_SUCCESS) {
    577  1.1      manu 			syslog(LOG_ERR, "pam_close_session: %s",
    578  1.1      manu 			    pam_strerror(pamh, pam_err));
    579  1.1      manu 			warnx("pam_close_session: %s",
    580  1.1      manu 			    pam_strerror(pamh, pam_err));
    581  1.1      manu 		}
    582  1.1      manu 		pam_end(pamh, PAM_SUCCESS);
    583  1.5  christos 		exit(EXIT_SUCCESS);
    584  1.1      manu 		break;
    585  1.1      manu 	}
    586  1.1      manu 
    587  1.1      manu 	/*
    588  1.1      manu 	 * The child: starting here, we don't have to care about
    589  1.1      manu 	 * handling PAM issues if we exit, the parent will do the
    590  1.1      manu 	 * job when we exit.
    591  1.1      manu          *
    592  1.1      manu 	 * Destroy environment unless user has requested its preservation.
    593  1.1      manu 	 * Try to preserve TERM anyway.
    594  1.1      manu 	 */
    595  1.1      manu 	saved_term = getenv("TERM");
    596  1.1      manu 	if (!pflag) {
    597  1.1      manu 		environ = envinit;
    598  1.1      manu 		if (saved_term)
    599  1.1      manu 			setenv("TERM", saved_term, 0);
    600  1.1      manu 	}
    601  1.1      manu 
    602  1.1      manu 	if (*pwd->pw_shell == '\0')
    603  1.1      manu 		pwd->pw_shell = _PATH_BSHELL;
    604  1.1      manu 
    605  1.1      manu 	shell = login_getcapstr(lc, "shell", pwd->pw_shell, pwd->pw_shell);
    606  1.1      manu 	if (*shell == '\0')
    607  1.1      manu 		shell = pwd->pw_shell;
    608  1.1      manu 
    609  1.1      manu 	if ((pwd->pw_shell = strdup(shell)) == NULL) {
    610  1.1      manu 		syslog(LOG_ERR, "Cannot alloc mem");
    611  1.5  christos 		exit(EXIT_FAILURE);
    612  1.1      manu 	}
    613  1.1      manu 
    614  1.1      manu 	(void)setenv("HOME", pwd->pw_dir, 1);
    615  1.1      manu 	(void)setenv("SHELL", pwd->pw_shell, 1);
    616  1.1      manu 	if (term[0] == '\0') {
    617  1.1      manu 		char *tt = (char *)stypeof(tty);
    618  1.1      manu 
    619  1.1      manu 		if (tt == NULL)
    620  1.1      manu 			tt = login_getcapstr(lc, "term", NULL, NULL);
    621  1.1      manu 
    622  1.1      manu 		/* unknown term -> "su" */
    623  1.1      manu 		(void)strlcpy(term, tt != NULL ? tt : "su", sizeof(term));
    624  1.1      manu 	}
    625  1.1      manu 	(void)setenv("TERM", term, 0);
    626  1.1      manu 	(void)setenv("LOGNAME", pwd->pw_name, 1);
    627  1.1      manu 	(void)setenv("USER", pwd->pw_name, 1);
    628  1.1      manu 
    629  1.1      manu 	/*
    630  1.1      manu 	 * Add PAM environement
    631  1.1      manu 	 */
    632  1.1      manu 	if ((pamenv = pam_getenvlist(pamh)) != NULL) {
    633  1.1      manu 		char **envitem;
    634  1.1      manu 
    635  1.1      manu 		for (envitem = pamenv; *envitem; envitem++) {
    636  1.1      manu 			putenv(*envitem);
    637  1.1      manu 			free(*envitem);
    638  1.1      manu 		}
    639  1.1      manu 
    640  1.1      manu 		free(pamenv);
    641  1.1      manu 	}
    642  1.1      manu 
    643  1.1      manu 	/* This drops root privs */
    644  1.1      manu 	if (setusercontext(lc, pwd, pwd->pw_uid,
    645  1.1      manu 	    (LOGIN_SETALL & ~LOGIN_SETLOGIN)) != 0) {
    646  1.1      manu 		syslog(LOG_ERR, "setusercontext failed");
    647  1.5  christos 		exit(EXIT_FAILURE);
    648  1.1      manu 	}
    649  1.1      manu 
    650  1.1      manu 	if (!quietlog) {
    651  1.1      manu 		char *fname;
    652  1.1      manu 
    653  1.1      manu 		fname = login_getcapstr(lc, "copyright", NULL, NULL);
    654  1.1      manu 		if (fname != NULL && access(fname, F_OK) == 0)
    655  1.1      manu 			motd(fname);
    656  1.1      manu 		else
    657  1.1      manu 			(void)printf("%s", copyrightstr);
    658  1.1      manu 
    659  1.1      manu                 fname = login_getcapstr(lc, "welcome", NULL, NULL);
    660  1.1      manu                 if (fname == NULL || access(fname, F_OK) != 0)
    661  1.1      manu                         fname = _PATH_MOTDFILE;
    662  1.1      manu                 motd(fname);
    663  1.1      manu 
    664  1.1      manu 		(void)snprintf(tbuf,
    665  1.1      manu 		    sizeof(tbuf), "%s/%s", _PATH_MAILDIR, pwd->pw_name);
    666  1.1      manu 		if (stat(tbuf, &st) == 0 && st.st_size != 0)
    667  1.1      manu 			(void)printf("You have %smail.\n",
    668  1.1      manu 			    (st.st_mtime > st.st_atime) ? "new " : "");
    669  1.1      manu 	}
    670  1.1      manu 
    671  1.1      manu 	login_close(lc);
    672  1.1      manu 
    673  1.1      manu 	(void)signal(SIGALRM, SIG_DFL);
    674  1.1      manu 	(void)signal(SIGQUIT, SIG_DFL);
    675  1.1      manu 	(void)signal(SIGINT, SIG_DFL);
    676  1.1      manu 	(void)signal(SIGTSTP, SIG_IGN);
    677  1.1      manu 
    678  1.1      manu 	tbuf[0] = '-';
    679  1.1      manu 	(void)strlcpy(tbuf + 1, (p = strrchr(pwd->pw_shell, '/')) ?
    680  1.1      manu 	    p + 1 : pwd->pw_shell, sizeof(tbuf) - 1);
    681  1.1      manu 
    682  1.8      matt 	execlp(pwd->pw_shell, tbuf, NULL);
    683  1.5  christos 	err(EXIT_FAILURE, "%s", pwd->pw_shell);
    684  1.1      manu }
    685  1.1      manu 
    686  1.1      manu #define	NBUFSIZ		(MAXLOGNAME + 1)
    687  1.1      manu 
    688  1.1      manu 
    689  1.1      manu void
    690  1.1      manu getloginname(void)
    691  1.1      manu {
    692  1.1      manu 	int ch;
    693  1.1      manu 	char *p;
    694  1.1      manu 	static char nbuf[NBUFSIZ];
    695  1.1      manu 
    696  1.1      manu 	for (;;) {
    697  1.1      manu 		(void)printf("login: ");
    698  1.1      manu 		for (p = nbuf; (ch = getchar()) != '\n'; ) {
    699  1.1      manu 			if (ch == EOF) {
    700  1.1      manu 				badlogin(username);
    701  1.5  christos 				exit(EXIT_SUCCESS);
    702  1.1      manu 			}
    703  1.1      manu 			if (p < nbuf + (NBUFSIZ - 1))
    704  1.1      manu 				*p++ = ch;
    705  1.1      manu 		}
    706  1.1      manu 		if (p > nbuf) {
    707  1.1      manu 			if (nbuf[0] == '-')
    708  1.1      manu 				(void)fprintf(stderr,
    709  1.1      manu 				    "login names may not start with '-'.\n");
    710  1.1      manu 			else {
    711  1.1      manu 				*p = '\0';
    712  1.1      manu 				username = nbuf;
    713  1.1      manu 				break;
    714  1.1      manu 			}
    715  1.1      manu 		}
    716  1.1      manu 	}
    717  1.1      manu }
    718  1.1      manu 
    719  1.1      manu int
    720  1.1      manu rootterm(char *ttyn)
    721  1.1      manu {
    722  1.1      manu 	struct ttyent *t;
    723  1.1      manu 
    724  1.1      manu 	return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE);
    725  1.1      manu }
    726  1.1      manu 
    727  1.1      manu jmp_buf motdinterrupt;
    728  1.1      manu 
    729  1.1      manu void
    730  1.1      manu motd(char *fname)
    731  1.1      manu {
    732  1.1      manu 	int fd, nchars;
    733  1.1      manu 	sig_t oldint;
    734  1.1      manu 	char tbuf[8192];
    735  1.1      manu 
    736  1.1      manu 	if ((fd = open(fname ? fname : _PATH_MOTDFILE, O_RDONLY, 0)) < 0)
    737  1.1      manu 		return;
    738  1.1      manu 	oldint = signal(SIGINT, sigint);
    739  1.1      manu 	if (setjmp(motdinterrupt) == 0)
    740  1.1      manu 		while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0)
    741  1.1      manu 			(void)write(fileno(stdout), tbuf, nchars);
    742  1.1      manu 	(void)signal(SIGINT, oldint);
    743  1.1      manu 	(void)close(fd);
    744  1.1      manu }
    745  1.1      manu 
    746  1.1      manu /* ARGSUSED */
    747  1.1      manu void
    748  1.1      manu sigint(int signo)
    749  1.1      manu {
    750  1.1      manu 
    751  1.1      manu 	longjmp(motdinterrupt, 1);
    752  1.1      manu }
    753  1.1      manu 
    754  1.1      manu /* ARGSUSED */
    755  1.1      manu void
    756  1.1      manu timedout(int signo)
    757  1.1      manu {
    758  1.1      manu 
    759  1.1      manu 	(void)fprintf(stderr, "Login timed out after %d seconds\n", timeout);
    760  1.5  christos 	exit(EXIT_SUCCESS);
    761  1.1      manu }
    762  1.1      manu 
    763  1.1      manu static void
    764  1.1      manu update_db(int quietlog)
    765  1.1      manu {
    766  1.1      manu 	if (nested != NULL) {
    767  1.1      manu 		if (hostname != NULL)
    768  1.1      manu 			syslog(LOG_NOTICE, "%s to %s on tty %s from %s",
    769  1.1      manu 			    nested, pwd->pw_name, tty, hostname);
    770  1.1      manu 		else
    771  1.1      manu 			syslog(LOG_NOTICE, "%s to %s on tty %s", nested,
    772  1.1      manu 			    pwd->pw_name, tty);
    773  1.1      manu 
    774  1.1      manu 	}
    775  1.1      manu 	if (hostname != NULL && have_ss == 0) {
    776  1.1      manu 		socklen_t len = sizeof(ss);
    777  1.1      manu 		(void)getpeername(STDIN_FILENO, (struct sockaddr *)&ss, &len);
    778  1.1      manu 	}
    779  1.1      manu 	(void)gettimeofday(&now, NULL);
    780  1.1      manu }
    781  1.1      manu 
    782  1.1      manu void
    783  1.1      manu badlogin(char *name)
    784  1.1      manu {
    785  1.1      manu 
    786  1.1      manu 	if (failures == 0)
    787  1.1      manu 		return;
    788  1.1      manu 	if (hostname) {
    789  1.1      manu 		syslog(LOG_NOTICE, "%d LOGIN FAILURE%s FROM %s",
    790  1.1      manu 		    failures, failures > 1 ? "S" : "", hostname);
    791  1.1      manu 		syslog(LOG_AUTHPRIV|LOG_NOTICE,
    792  1.1      manu 		    "%d LOGIN FAILURE%s FROM %s, %s",
    793  1.1      manu 		    failures, failures > 1 ? "S" : "", hostname, name);
    794  1.1      manu 	} else {
    795  1.1      manu 		syslog(LOG_NOTICE, "%d LOGIN FAILURE%s ON %s",
    796  1.1      manu 		    failures, failures > 1 ? "S" : "", tty);
    797  1.1      manu 		syslog(LOG_AUTHPRIV|LOG_NOTICE,
    798  1.1      manu 		    "%d LOGIN FAILURE%s ON %s, %s",
    799  1.1      manu 		    failures, failures > 1 ? "S" : "", tty, name);
    800  1.1      manu 	}
    801  1.1      manu }
    802  1.1      manu 
    803  1.1      manu const char *
    804  1.1      manu stypeof(const char *ttyid)
    805  1.1      manu {
    806  1.1      manu 	struct ttyent *t;
    807  1.1      manu 
    808  1.1      manu 	return (ttyid && (t = getttynam(ttyid)) ? t->ty_type : NULL);
    809  1.1      manu }
    810  1.1      manu 
    811  1.1      manu void
    812  1.1      manu sleepexit(int eval)
    813  1.1      manu {
    814  1.1      manu 
    815  1.1      manu 	(void)sleep(5);
    816  1.1      manu 	exit(eval);
    817  1.1      manu }
    818  1.1      manu 
    819  1.1      manu void
    820  1.1      manu decode_ss(const char *arg)
    821  1.1      manu {
    822  1.1      manu 	struct sockaddr_storage *ssp;
    823  1.1      manu 	size_t len = strlen(arg);
    824  1.1      manu 
    825  1.1      manu 	if (len > sizeof(*ssp) * 4 + 1 || len < sizeof(*ssp))
    826  1.5  christos 		errx(EXIT_FAILURE, "Bad argument");
    827  1.1      manu 
    828  1.1      manu 	if ((ssp = malloc(len)) == NULL)
    829  1.5  christos 		err(EXIT_FAILURE, NULL);
    830  1.1      manu 
    831  1.1      manu 	if (strunvis((char *)ssp, arg) != sizeof(*ssp))
    832  1.5  christos 		errx(EXIT_FAILURE, "Decoding error");
    833  1.1      manu 
    834  1.1      manu 	(void)memcpy(&ss, ssp, sizeof(ss));
    835  1.1      manu 	have_ss = 1;
    836  1.1      manu }
    837  1.1      manu 
    838  1.1      manu void
    839  1.1      manu usage(void)
    840  1.1      manu {
    841  1.1      manu 	(void)fprintf(stderr,
    842  1.1      manu 	    "Usage: %s [-Ffps] [-a address] [-h hostname] [username]\n",
    843  1.1      manu 	    getprogname());
    844  1.5  christos 	exit(EXIT_FAILURE);
    845  1.1      manu }
    846