usr.bin/login/login_pam.c

   1 /*     $NetBSD: login_pam.c,v 1.19 2008/07/21 14:19:23 lukem Exp $       */
   2
   3 /*-
   4  * Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   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.
  18  *
  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.
  30  */
  31
  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 */
  37
  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 1.19 2008/07/21 14:19:23 lukem Exp $");
  43 #endif /* not lint */
  44
  45 /*
  46  * login [ name ]
  47  * login -h hostname    (for telnetd, etc.)
  48  * login -f name        (for pre-authenticated login: datakit, xterm, etc.)
  49  */
  50
  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>
  58
  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>
  76
  77 #include <security/pam_appl.h>
  78 #include <security/openpam.h>
  79
  80 #include "pathnames.h"
  81 #include "common.h"
  82
  83 #if 0
  84 static int       rootterm(char *);
  85 #endif
  86 static void      usage(void) __attribute__((__noreturn__));
  87
  88 static struct pam_conv pamc = { openpam_ttyconv, NULL };
  89
  90 #define TTYGRPNAME      "tty"           /* name of group to own ttys */
  91
  92 #define DEFAULT_BACKOFF 3
  93 #define DEFAULT_RETRIES 10
  94
  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;
 100
 101 int
 102 main(int argc, char *argv[])
 103 {
 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;
 127
 128         tbuf[0] = '\0';
 129         pwprompt = NULL;
 130         nested = NULL;
 131         need_chpass = require_chpass = 0;
 132
 133         oabrt = signal(SIGABRT, SIG_IGN);
 134         oalrm = signal(SIGALRM, timedout);
 135         oint = signal(SIGINT, SIG_IGN);
 136         oquit = signal(SIGQUIT, SIG_IGN);
 137
 138         (void)alarm(timeout);
 139         (void)setpriority(PRIO_PROCESS, 0, 0);
 140
 141         openlog("login", 0, LOG_AUTH);
 142
 143         /*
 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.
 150          */
 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';
 157
 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");
 167                         }
 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");
 177                         }
 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;
 190                 }
 191
 192         setproctitle(NULL);
 193         argc -= optind;
 194         argv += optind;
 195
 196         if (*argv) {
 197                 username = *argv;
 198                 ask = 0;
 199         } else
 200                 ask = 1;
 201
 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
 208
 209         ttyn = ttyname(STDIN_FILENO);
 210         if (ttyn == NULL || *ttyn == '\0') {
 211                 (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY);
 212                 ttyn = tname;
 213         }
 214         if ((tty = strstr(ttyn, "/pts/")) != NULL)
 215                 ++tty;
 216         else if ((tty = strrchr(ttyn, '/')) != NULL)
 217                 ++tty;
 218         else
 219                 tty = ttyn;
 220
 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);
 226                 }
 227         }
 228
 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;
 237         }
 238
 239
 240         for (cnt = 0;; ask = 1) {
 241                 if (ask) {
 242                         fflag = 0;
 243                         getloginname();
 244                 }
 245                 rootlogin = 0;
 246                 auth_passed = 0;
 247                 if (strlen(username) > MAXLOGNAME)
 248                         username[MAXLOGNAME] = '\0';
 249
 250                 /*
 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).
 254                  */
 255                 if (failures && strcmp(tbuf, username)) {
 256                         if (failures > (pwd ? 0 : 1))
 257                                 badlogin(tbuf);
 258                         failures = 0;
 259                 }
 260
 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)
 267
 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");
 276                 }
 277
 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)
 283
 284                 /*
 285                  * Fill hostname tty, and nested user
 286                  */
 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);
 293
 294                 /*
 295                  * Don't check for errors, because we don't want to give
 296                  * out any information.
 297                  */
 298                 pwd = NULL;
 299                 (void)getpwnam_r(username, &pwres, pwbuf, sizeof(pwbuf), &pwd);
 300
 301                 /*
 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.
 305                  */
 306                 lc = login_getclass(pwd ? pwd->pw_class : NULL);
 307
 308                 /*
 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.
 313                  */
 314                 if (pwd) {
 315                         if (pwd->pw_uid == 0)
 316                                 rootlogin = 1;
 317
 318                         if (fflag && (uid == 0 || uid == pwd->pw_uid)) {
 319                                 /* already authenticated */
 320                                 auth_passed = 1;
 321                                 goto skip_auth;
 322                         }
 323                 }
 324
 325                 (void)setpriority(PRIO_PROCESS, 0, -4);
 326
 327                 switch(pam_err = pam_authenticate(pamh, pam_silent)) {
 328                 case PAM_SUCCESS:
 329                         /*
 330                          * PAM can change the user, refresh
 331                          * username, pwd, and lc.
 332                          */
 333                         pam_err = pam_get_item(pamh, PAM_USER, &newuser);
 334                         if (pam_err != PAM_SUCCESS)
 335                                 PAM_END("pam_get_item(PAM_USER)");
 336
 337                         username = (char *)newuser;
 338                         /*
 339                          * Don't check for errors, because we don't want to give
 340                          * out any information.
 341                          */
 342                         pwd = NULL;
 343                         (void)getpwnam_r(username, &pwres, pwbuf, sizeof(pwbuf),
 344                             &pwd);
 345                         lc = login_getpwclass(pwd);
 346                         auth_passed = 1;
 347
 348                         switch (pam_err = pam_acct_mgmt(pamh, pam_silent)) {
 349                         case PAM_SUCCESS:
 350                                 break;
 351
 352                         case PAM_NEW_AUTHTOK_REQD:
 353                                 pam_err = pam_chauthtok(pamh,
 354                                     pam_silent|PAM_CHANGE_EXPIRED_AUTHTOK);
 355
 356                                 if (pam_err != PAM_SUCCESS)
 357                                         PAM_END("pam_chauthtok");
 358                                 break;
 359
 360                         case PAM_AUTH_ERR:
 361                         case PAM_USER_UNKNOWN:
 362                         case PAM_MAXTRIES:
 363                                 auth_passed = 0;
 364                                 break;
 365
 366                         default:
 367                                 PAM_END("pam_acct_mgmt");
 368                                 break;
 369                         }
 370                         break;
 371
 372                 case PAM_AUTH_ERR:
 373                 case PAM_USER_UNKNOWN:
 374                 case PAM_MAXTRIES:
 375                         auth_passed = 0;
 376                         break;
 377
 378                 default:
 379                         PAM_END("pam_authenticate");
 380                         break;
 381                 }
 382
 383                 (void)setpriority(PRIO_PROCESS, 0, 0);
 384
 385 skip_auth:
 386                 /*
 387                  * If the user exists and authentication passed,
 388                  * get out of the loop and login the user.
 389                  */
 390                 if (pwd && auth_passed)
 391                         break;
 392
 393                 (void)printf("Login incorrect or refused on this terminal.\n");
 394                 failures++;
 395                 cnt++;
 396                 /*
 397                  * We allow login_retries tries, but after login_backoff
 398                  * we start backing off.  These default to 10 and 3
 399                  * respectively.
 400                  */
 401                 if (cnt > login_backoff) {
 402                         if (cnt >= login_retries) {
 403                                 badlogin(username);
 404                                 pam_end(pamh, PAM_SUCCESS);
 405                                 sleepexit(EXIT_FAILURE);
 406                         }
 407                         sleep((u_int)((cnt - login_backoff) * 5));
 408                 }
 409         }
 410
 411         /* committed to login -- turn off timeout */
 412         (void)alarm((u_int)0);
 413
 414         endpwent();
 415
 416         quietlog = login_getcapbool(lc, "hushlogin", 0);
 417
 418         /*
 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
 422          */
 423         saved_uid = geteuid();
 424         saved_gid = getegid();
 425         nsaved_gids = getgroups(NGROUPS_MAX, saved_gids);
 426
 427         (void)setegid(pwd->pw_gid);
 428         initgroups(username, pwd->pw_gid);
 429         (void)seteuid(pwd->pw_uid);
 430
 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);
 437                 }
 438
 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);
 443                 }
 444                 pwd->pw_dir = "/";
 445                 (void)printf("Logging in with home = \"/\".\n");
 446         }
 447
 448         if (!quietlog) {
 449                 quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0;
 450                 pam_silent = quietlog ? PAM_SILENT : 0;
 451         }
 452
 453         /* regain special privileges */
 454         setegid(saved_gid);
 455         setgroups(nsaved_gids, saved_gids);
 456         seteuid(saved_uid);
 457
 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);
 461
 462         if (ttyaction(ttyn, "login", pwd->pw_name))
 463                 (void)printf("Warning: ttyaction failed.\n");
 464
 465         /* Nothing else left to fail -- really log in. */
 466         update_db(quietlog, rootlogin, fflag);
 467
 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);
 473         }
 474
 475         if (tty[sizeof("tty")-1] == 'd')
 476                 syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name);
 477
 478
 479         /*
 480          * Establish groups
 481          */
 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);
 486         }
 487
 488         pam_err = pam_setcred(pamh, pam_silent|PAM_ESTABLISH_CRED);
 489         if (pam_err != PAM_SUCCESS)
 490                 PAM_END("pam_setcred");
 491
 492         pam_err = pam_open_session(pamh, pam_silent);
 493         if (pam_err != PAM_SUCCESS)
 494                 PAM_END("pam_open_session");
 495
 496         /*
 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.
 500          */
 501
 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));
 510                 }
 511                 syslog(LOG_ERR, "fork failed: %m");
 512                 warn("fork failed");
 513                 pam_end(pamh, pam_err);
 514                 exit(EXIT_FAILURE);
 515                 break;
 516
 517         case 0: /* Child */
 518                 break;
 519
 520         default:
 521                 /*
 522                  * Parent: wait for the child to terminate
 523                  * and call pam_close_session.
 524                  */
 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));
 533                         }
 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);
 540                 }
 541
 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));
 551                 }
 552                 pam_end(pamh, PAM_SUCCESS);
 553                 exit(EXIT_SUCCESS);
 554                 break;
 555         }
 556
 557         /*
 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.
 561          *
 562          * Destroy environment unless user has requested its preservation.
 563          * Try to preserve TERM anyway.
 564          */
 565         saved_term = getenv("TERM");
 566         if (!pflag) {
 567                 environ = envinit;
 568                 if (saved_term)
 569                         setenv("TERM", saved_term, 0);
 570         }
 571
 572         if (*pwd->pw_shell == '\0')
 573                 pwd->pw_shell = _PATH_BSHELL;
 574
 575         shell = login_getcapstr(lc, "shell", pwd->pw_shell, pwd->pw_shell);
 576         if (*shell == '\0')
 577                 shell = pwd->pw_shell;
 578
 579         if ((pwd->pw_shell = strdup(shell)) == NULL) {
 580                 syslog(LOG_ERR, "Cannot alloc mem");
 581                 exit(EXIT_FAILURE);
 582         }
 583
 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);
 588
 589                 if (tt == NULL)
 590                         tt = login_getcapstr(lc, "term", NULL, NULL);
 591
 592                 /* unknown term -> "su" */
 593                 (void)strlcpy(term, tt != NULL ? tt : "su", sizeof(term));
 594         }
 595         (void)setenv("TERM", term, 0);
 596         (void)setenv("LOGNAME", pwd->pw_name, 1);
 597         (void)setenv("USER", pwd->pw_name, 1);
 598
 599         /*
 600          * Add PAM environement
 601          */
 602         if ((pamenv = pam_getenvlist(pamh)) != NULL) {
 603                 char **envitem;
 604
 605                 for (envitem = pamenv; *envitem; envitem++) {
 606                         putenv(*envitem);
 607                         free(*envitem);
 608                 }
 609
 610                 free(pamenv);
 611         }
 612
 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);
 618         }
 619
 620         if (!quietlog) {
 621                 char *fname;
 622
 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);
 628
 629                 fname = login_getcapstr(lc, "welcome", NULL, NULL);
 630                 if (fname == NULL || access(fname, F_OK) != 0)
 631                         fname = _PATH_MOTDFILE;
 632                 motd(fname);
 633
 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 " : "");
 639         }
 640
 641         login_close(lc);
 642
 643
 644         tbuf[0] = '-';
 645         (void)strlcpy(tbuf + 1, (p = strrchr(pwd->pw_shell, '/')) ?
 646             p + 1 : pwd->pw_shell, sizeof(tbuf) - 1);
 647
 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);
 653
 654         execlp(pwd->pw_shell, tbuf, NULL);
 655         err(EXIT_FAILURE, "%s", pwd->pw_shell);
 656 }
 657
 658 static void
 659 usage(void)
 660 {
 661         (void)fprintf(stderr,
 662             "Usage: %s [-fp] [-a address] [-h hostname] [username]\n",
 663             getprogname());
 664         exit(EXIT_FAILURE);
 665 }
 666
 667 #if 0
 668 static int
 669 rootterm(char *ttyn)
 670 {
 671         struct ttyent *t;
 672
 673         return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE);
 674 }
 675 #endif