usr.bin/login/login.c

   1 /*      $NetBSD: login.c,v 1.96 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.c,v 1.96 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 <sysexits.h>
  74 #ifdef SUPPORT_UTMP
  75 #include <utmp.h>
  76 #endif
  77 #ifdef SUPPORT_UTMPX
  78 #include <utmpx.h>
  79 #endif
  80 #include <util.h>
  81 #ifdef SKEY
  82 #include <skey.h>
  83 #endif
  84 #ifdef KERBEROS5
  85 #include <krb5/krb5.h>
  86 #include <com_err.h>
  87 #endif
  88 #ifdef LOGIN_CAP
  89 #include <login_cap.h>
  90 #endif
  91 #include <vis.h>
  92
  93 #include "pathnames.h"
  94 #include "common.h"
  95
  96 #ifdef KERBEROS5
  97 int login_krb5_forwardable_tgt = 0;
  98 static int login_krb5_get_tickets = 1;
  99 static int login_krb5_retain_ccache = 0;
 100 #endif
 101
 102 static void      checknologin(char *);
 103 #ifdef KERBEROS5
 104 int      k5login(struct passwd *, char *, char *, char *);
 105 void     k5destroy(void);
 106 int      k5_read_creds(char*);
 107 int      k5_write_creds(void);
 108 #endif
 109 #if defined(KERBEROS5)
 110 static void      dofork(void);
 111 #endif
 112 static void      usage(void);
 113
 114 #define TTYGRPNAME      "tty"           /* name of group to own ttys */
 115
 116 #define DEFAULT_BACKOFF 3
 117 #define DEFAULT_RETRIES 10
 118
 119 #if defined(KERBEROS5)
 120 int     has_ccache = 0;
 121 static int      notickets = 1;
 122 static char     *instance;
 123 extern krb5_context kcontext;
 124 extern int      have_forward;
 125 extern char     *krb5tkfile_env;
 126 extern int      krb5_configured;
 127 #endif
 128
 129 #if defined(KERBEROS5)
 130 #define KERBEROS_CONFIGURED     krb5_configured
 131 #endif
 132
 133 extern char **environ;
 134
 135 int
 136 main(int argc, char *argv[])
 137 {
 138         struct group *gr;
 139         struct stat st;
 140         int ask, ch, cnt, fflag, hflag, pflag, sflag, quietlog, rootlogin, rval;
 141         int Fflag;
 142         uid_t uid, saved_uid;
 143         gid_t saved_gid, saved_gids[NGROUPS_MAX];
 144         int nsaved_gids;
 145         char *domain, *p, *ttyn, *pwprompt;
 146         char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10];
 147         char localhost[MAXHOSTNAMELEN + 1];
 148         int need_chpass, require_chpass;
 149         int login_retries = DEFAULT_RETRIES,
 150             login_backoff = DEFAULT_BACKOFF;
 151         time_t pw_warntime = _PASSWORD_WARNDAYS * SECSPERDAY;
 152 #ifdef KERBEROS5
 153         krb5_error_code kerror;
 154 #endif
 155 #if defined(KERBEROS5)
 156         int got_tickets = 0;
 157 #endif
 158 #ifdef LOGIN_CAP
 159         char *shell = NULL;
 160         login_cap_t *lc = NULL;
 161 #endif
 162
 163         tbuf[0] = '\0';
 164         rval = 0;
 165         pwprompt = NULL;
 166         nested = NULL;
 167         need_chpass = require_chpass = 0;
 168
 169         (void)signal(SIGALRM, timedout);
 170         (void)alarm(timeout);
 171         (void)signal(SIGQUIT, SIG_IGN);
 172         (void)signal(SIGINT, SIG_IGN);
 173         (void)setpriority(PRIO_PROCESS, 0, 0);
 174
 175         openlog("login", 0, LOG_AUTH);
 176
 177         /*
 178          * -p is used by getty to tell login not to destroy the environment
 179          * -f is used to skip a second login authentication
 180          * -h is used by other servers to pass the name of the remote host to
 181          *    login so that it may be placed in utmp/utmpx and wtmp/wtmpx
 182          * -a in addition to -h, a server may supply -a to pass the actual
 183          *    server address.
 184          * -s is used to force use of S/Key or equivalent.
 185          */
 186         domain = NULL;
 187         if (gethostname(localhost, sizeof(localhost)) < 0)
 188                 syslog(LOG_ERR, "couldn't get local hostname: %m");
 189         else
 190                 domain = strchr(localhost, '.');
 191         localhost[sizeof(localhost) - 1] = '\0';
 192
 193         Fflag = fflag = hflag = pflag = sflag = 0;
 194         have_ss = 0;
 195 #ifdef KERBEROS5
 196         have_forward = 0;
 197 #endif
 198         uid = getuid();
 199         while ((ch = getopt(argc, argv, "a:Ffh:ps")) != -1)
 200                 switch (ch) {
 201                 case 'a':
 202                         if (uid)
 203                                 errx(EXIT_FAILURE, "-a option: %s", strerror(EPERM));
 204                         decode_ss(optarg);
 205 #ifdef notdef
 206                         (void)sockaddr_snprintf(optarg,
 207                             sizeof(struct sockaddr_storage), "%a", (void *)&ss);
 208 #endif
 209                         break;
 210                 case 'F':
 211                         Fflag = 1;
 212                         /* FALLTHROUGH */
 213                 case 'f':
 214                         fflag = 1;
 215                         break;
 216                 case 'h':
 217                         if (uid)
 218                                 errx(EXIT_FAILURE, "-h option: %s", strerror(EPERM));
 219                         hflag = 1;
 220 #ifdef notdef
 221                         if (domain && (p = strchr(optarg, '.')) != NULL &&
 222                             strcasecmp(p, domain) == 0)
 223                                 *p = '\0';
 224 #endif
 225                         hostname = optarg;
 226                         break;
 227                 case 'p':
 228                         pflag = 1;
 229                         break;
 230                 case 's':
 231                         sflag = 1;
 232                         break;
 233                 default:
 234                 case '?':
 235                         usage();
 236                         break;
 237                 }
 238
 239         setproctitle(NULL);
 240         argc -= optind;
 241         argv += optind;
 242
 243         if (*argv) {
 244                 username = *argv;
 245                 ask = 0;
 246         } else
 247                 ask = 1;
 248
 249 #ifdef F_CLOSEM
 250         (void)fcntl(3, F_CLOSEM, 0);
 251 #else
 252         for (cnt = getdtablesize(); cnt > 2; cnt--)
 253                 (void)close(cnt);
 254 #endif
 255
 256         ttyn = ttyname(STDIN_FILENO);
 257         if (ttyn == NULL || *ttyn == '\0') {
 258                 (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY);
 259                 ttyn = tname;
 260         }
 261         if ((tty = strstr(ttyn, "/pts/")) != NULL)
 262                 ++tty;
 263         else if ((tty = strrchr(ttyn, '/')) != NULL)
 264                 ++tty;
 265         else
 266                 tty = ttyn;
 267
 268         if (issetugid()) {
 269                 nested = strdup(user_from_uid(getuid(), 0));
 270                 if (nested == NULL) {
 271                         syslog(LOG_ERR, "strdup: %m");
 272                         sleepexit(EXIT_FAILURE);
 273                 }
 274         }
 275
 276 #ifdef LOGIN_CAP
 277         /* Get "login-retries" and "login-backoff" from default class */
 278         if ((lc = login_getclass(NULL)) != NULL) {
 279                 login_retries = (int)login_getcapnum(lc, "login-retries",
 280                     DEFAULT_RETRIES, DEFAULT_RETRIES);
 281                 login_backoff = (int)login_getcapnum(lc, "login-backoff",
 282                     DEFAULT_BACKOFF, DEFAULT_BACKOFF);
 283                 login_close(lc);
 284                 lc = NULL;
 285         }
 286 #endif
 287
 288 #ifdef KERBEROS5
 289         kerror = krb5_init_context(&kcontext);
 290         if (kerror) {
 291                 /*
 292                  * If Kerberos is not configured, that is, we are
 293                  * not using Kerberos, do not log the error message.
 294                  * However, if Kerberos is configured,  and the
 295                  * context init fails for some other reason, we need
 296                  * to issue a no tickets warning to the user when the
 297                  * login succeeds.
 298                  */
 299                 if (kerror != ENXIO) {  /* XXX NetBSD-local Heimdal hack */
 300                         syslog(LOG_NOTICE,
 301                             "%s when initializing Kerberos context",
 302                             error_message(kerror));
 303                         krb5_configured = 1;
 304                 }
 305                 login_krb5_get_tickets = 0;
 306         }
 307 #endif /* KERBEROS5 */
 308
 309         for (cnt = 0;; ask = 1) {
 310 #if defined(KERBEROS5)
 311                 if (login_krb5_get_tickets)
 312                         k5destroy();
 313 #endif
 314                 if (ask) {
 315                         fflag = 0;
 316                         getloginname();
 317                 }
 318                 rootlogin = 0;
 319 #ifdef KERBEROS5
 320                 if ((instance = strchr(username, '/')) != NULL)
 321                         *instance++ = '\0';
 322                 else
 323                         instance = "";
 324 #endif
 325                 if (strlen(username) > MAXLOGNAME)
 326                         username[MAXLOGNAME] = '\0';
 327
 328                 /*
 329                  * Note if trying multiple user names; log failures for
 330                  * previous user name, but don't bother logging one failure
 331                  * for nonexistent name (mistyped username).
 332                  */
 333                 if (failures && strcmp(tbuf, username)) {
 334                         if (failures > (pwd ? 0 : 1))
 335                                 badlogin(tbuf);
 336                         failures = 0;
 337                 }
 338                 (void)strlcpy(tbuf, username, sizeof(tbuf));
 339
 340                 pwd = getpwnam(username);
 341
 342 #ifdef LOGIN_CAP
 343                 /*
 344                  * Establish the class now, before we might goto
 345                  * within the next block. pwd can be NULL since it
 346                  * falls back to the "default" class if it is.
 347                  */
 348                 lc = login_getclass(pwd ? pwd->pw_class : NULL);
 349 #endif
 350                 /*
 351                  * if we have a valid account name, and it doesn't have a
 352                  * password, or the -f option was specified and the caller
 353                  * is root or the caller isn't changing their uid, don't
 354                  * authenticate.
 355                  */
 356                 if (pwd) {
 357                         if (pwd->pw_uid == 0)
 358                                 rootlogin = 1;
 359
 360                         if (fflag && (uid == 0 || uid == pwd->pw_uid)) {
 361                                 /* already authenticated */
 362 #ifdef KERBEROS5
 363                                 if (login_krb5_get_tickets && Fflag)
 364                                         k5_read_creds(username);
 365 #endif
 366                                 break;
 367                         } else if (pwd->pw_passwd[0] == '\0') {
 368                                 /* pretend password okay */
 369                                 rval = 0;
 370                                 goto ttycheck;
 371                         }
 372                 }
 373
 374                 fflag = 0;
 375
 376                 (void)setpriority(PRIO_PROCESS, 0, -4);
 377
 378 #ifdef SKEY
 379                 if (skey_haskey(username) == 0) {
 380                         static char skprompt[80];
 381                         const char *skinfo = skey_keyinfo(username);
 382
 383                         (void)snprintf(skprompt, sizeof(skprompt),
 384                             "Password [ %s ]:",
 385                             skinfo ? skinfo : "error getting challenge");
 386                         pwprompt = skprompt;
 387                 } else
 388 #endif
 389                         pwprompt = "Password:";
 390
 391                 p = getpass(pwprompt);
 392
 393                 if (pwd == NULL) {
 394                         rval = 1;
 395                         goto skip;
 396                 }
 397 #ifdef KERBEROS5
 398                 if (login_krb5_get_tickets &&
 399                     k5login(pwd, instance, localhost, p) == 0) {
 400                         rval = 0;
 401                         got_tickets = 1;
 402                 }
 403 #endif
 404 #if defined(KERBEROS5)
 405                 if (got_tickets)
 406                         goto skip;
 407 #endif
 408 #ifdef SKEY
 409                 if (skey_haskey(username) == 0 &&
 410                     skey_passcheck(username, p) != -1) {
 411                         rval = 0;
 412                         goto skip;
 413                 }
 414 #endif
 415                 if (!sflag && *pwd->pw_passwd != '\0' &&
 416                     !strcmp(crypt(p, pwd->pw_passwd), pwd->pw_passwd)) {
 417                         rval = 0;
 418                         require_chpass = 1;
 419                         goto skip;
 420                 }
 421                 rval = 1;
 422
 423         skip:
 424                 memset(p, 0, strlen(p));
 425
 426                 (void)setpriority(PRIO_PROCESS, 0, 0);
 427
 428         ttycheck:
 429                 /*
 430                  * If trying to log in as root without Kerberos,
 431                  * but with insecure terminal, refuse the login attempt.
 432                  */
 433                 if (pwd && !rval && rootlogin && !rootterm(tty)) {
 434                         (void)printf("Login incorrect or refused on this "
 435                             "terminal.\n");
 436                         if (hostname)
 437                                 syslog(LOG_NOTICE,
 438                                     "LOGIN %s REFUSED FROM %s ON TTY %s",
 439                                     pwd->pw_name, hostname, tty);
 440                         else
 441                                 syslog(LOG_NOTICE,
 442                                     "LOGIN %s REFUSED ON TTY %s",
 443                                      pwd->pw_name, tty);
 444                         continue;
 445                 }
 446
 447                 if (pwd && !rval)
 448                         break;
 449
 450                 (void)printf("Login incorrect or refused on this "
 451                     "terminal.\n");
 452                 failures++;
 453                 cnt++;
 454                 /*
 455                  * We allow login_retries tries, but after login_backoff
 456                  * we start backing off.  These default to 10 and 3
 457                  * respectively.
 458                  */
 459                 if (cnt > login_backoff) {
 460                         if (cnt >= login_retries) {
 461                                 badlogin(username);
 462                                 sleepexit(EXIT_FAILURE);
 463                         }
 464                         sleep((u_int)((cnt - login_backoff) * 5));
 465                 }
 466         }
 467
 468         /* committed to login -- turn off timeout */
 469         (void)alarm((u_int)0);
 470
 471         endpwent();
 472
 473         /* if user not super-user, check for disabled logins */
 474 #ifdef LOGIN_CAP
 475         if (!login_getcapbool(lc, "ignorenologin", rootlogin))
 476                 checknologin(login_getcapstr(lc, "nologin", NULL, NULL));
 477 #else
 478         if (!rootlogin)
 479                 checknologin(NULL);
 480 #endif
 481
 482 #ifdef LOGIN_CAP
 483         quietlog = login_getcapbool(lc, "hushlogin", 0);
 484 #else
 485         quietlog = 0;
 486 #endif
 487         /* Temporarily give up special privileges so we can change */
 488         /* into NFS-mounted homes that are exported for non-root */
 489         /* access and have mode 7x0 */
 490         saved_uid = geteuid();
 491         saved_gid = getegid();
 492         nsaved_gids = getgroups(NGROUPS_MAX, saved_gids);
 493
 494         (void)setegid(pwd->pw_gid);
 495         initgroups(username, pwd->pw_gid);
 496         (void)seteuid(pwd->pw_uid);
 497
 498         if (chdir(pwd->pw_dir) < 0) {
 499 #ifdef LOGIN_CAP
 500                 if (login_getcapbool(lc, "requirehome", 0)) {
 501                         (void)printf("Home directory %s required\n",
 502                             pwd->pw_dir);
 503                         sleepexit(EXIT_FAILURE);
 504                 }
 505 #endif
 506                 (void)printf("No home directory %s!\n", pwd->pw_dir);
 507                 if (chdir("/") == -1)
 508                         exit(EXIT_FAILURE);
 509                 pwd->pw_dir = "/";
 510                 (void)printf("Logging in with home = \"/\".\n");
 511         }
 512
 513         if (!quietlog)
 514                 quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0;
 515
 516         /* regain special privileges */
 517         (void)seteuid(saved_uid);
 518         setgroups(nsaved_gids, saved_gids);
 519         (void)setegid(saved_gid);
 520
 521 #ifdef LOGIN_CAP
 522         pw_warntime = login_getcaptime(lc, "password-warn",
 523                 _PASSWORD_WARNDAYS * SECSPERDAY,
 524                 _PASSWORD_WARNDAYS * SECSPERDAY);
 525 #endif
 526
 527         (void)gettimeofday(&now, (struct timezone *)NULL);
 528         if (pwd->pw_expire) {
 529                 if (now.tv_sec >= pwd->pw_expire) {
 530                         (void)printf("Sorry -- your account has expired.\n");
 531                         sleepexit(EXIT_FAILURE);
 532                 } else if (pwd->pw_expire - now.tv_sec < pw_warntime &&
 533                     !quietlog)
 534                         (void)printf("Warning: your account expires on %s",
 535                             ctime(&pwd->pw_expire));
 536         }
 537         if (pwd->pw_change) {
 538                 if (pwd->pw_change == _PASSWORD_CHGNOW)
 539                         need_chpass = 1;
 540                 else if (now.tv_sec >= pwd->pw_change) {
 541                         (void)printf("Sorry -- your password has expired.\n");
 542                         sleepexit(EXIT_FAILURE);
 543                 } else if (pwd->pw_change - now.tv_sec < pw_warntime &&
 544                     !quietlog)
 545                         (void)printf("Warning: your password expires on %s",
 546                             ctime(&pwd->pw_change));
 547
 548         }
 549         /* Nothing else left to fail -- really log in. */
 550         update_db(quietlog, rootlogin, fflag);
 551
 552         (void)chown(ttyn, pwd->pw_uid,
 553             (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid);
 554
 555         if (ttyaction(ttyn, "login", pwd->pw_name))
 556                 (void)printf("Warning: ttyaction failed.\n");
 557
 558 #if defined(KERBEROS5)
 559         /* Fork so that we can call kdestroy */
 560         if (! login_krb5_retain_ccache && has_ccache)
 561                 dofork();
 562 #endif
 563
 564         /* Destroy environment unless user has requested its preservation. */
 565         if (!pflag)
 566                 environ = envinit;
 567
 568 #ifdef LOGIN_CAP
 569         if (nested == NULL && setusercontext(lc, pwd, pwd->pw_uid,
 570             LOGIN_SETLOGIN) != 0) {
 571                 syslog(LOG_ERR, "setusercontext failed");
 572                 exit(EXIT_FAILURE);
 573         }
 574         if (setusercontext(lc, pwd, pwd->pw_uid,
 575             (LOGIN_SETALL & ~(LOGIN_SETPATH|LOGIN_SETLOGIN))) != 0) {
 576                 syslog(LOG_ERR, "setusercontext failed");
 577                 exit(EXIT_FAILURE);
 578         }
 579 #else
 580         (void)setgid(pwd->pw_gid);
 581
 582         initgroups(username, pwd->pw_gid);
 583
 584         if (nested == NULL && setlogin(pwd->pw_name) < 0)
 585                 syslog(LOG_ERR, "setlogin() failure: %m");
 586
 587         /* Discard permissions last so can't get killed and drop core. */
 588         if (rootlogin)
 589                 (void)setuid(0);
 590         else
 591                 (void)setuid(pwd->pw_uid);
 592 #endif
 593
 594         if (*pwd->pw_shell == '\0')
 595                 pwd->pw_shell = _PATH_BSHELL;
 596 #ifdef LOGIN_CAP
 597         if ((shell = login_getcapstr(lc, "shell", NULL, NULL)) != NULL) {
 598                 if ((shell = strdup(shell)) == NULL) {
 599                         syslog(LOG_ERR, "Cannot alloc mem");
 600                         sleepexit(EXIT_FAILURE);
 601                 }
 602                 pwd->pw_shell = shell;
 603         }
 604 #endif
 605
 606         (void)setenv("HOME", pwd->pw_dir, 1);
 607         (void)setenv("SHELL", pwd->pw_shell, 1);
 608         if (term[0] == '\0') {
 609                 char *tt = (char *)stypeof(tty);
 610 #ifdef LOGIN_CAP
 611                 if (tt == NULL)
 612                         tt = login_getcapstr(lc, "term", NULL, NULL);
 613 #endif
 614                 /* unknown term -> "su" */
 615                 (void)strlcpy(term, tt != NULL ? tt : "su", sizeof(term));
 616         }
 617         (void)setenv("TERM", term, 0);
 618         (void)setenv("LOGNAME", pwd->pw_name, 1);
 619         (void)setenv("USER", pwd->pw_name, 1);
 620
 621 #ifdef LOGIN_CAP
 622         setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETPATH);
 623 #else
 624         (void)setenv("PATH", _PATH_DEFPATH, 0);
 625 #endif
 626
 627 #ifdef KERBEROS5
 628         if (krb5tkfile_env)
 629                 (void)setenv("KRB5CCNAME", krb5tkfile_env, 1);
 630 #endif
 631
 632         if (tty[sizeof("tty")-1] == 'd')
 633                 syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name);
 634
 635         /* If fflag is on, assume caller/authenticator has logged root login. */
 636         if (rootlogin && fflag == 0) {
 637                 if (hostname)
 638                         syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s",
 639                             username, tty, hostname);
 640                 else
 641                         syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s",
 642                             username, tty);
 643         }
 644
 645 #if defined(KERBEROS5)
 646         if (KERBEROS_CONFIGURED && !quietlog && notickets == 1)
 647                 (void)printf("Warning: no Kerberos tickets issued.\n");
 648 #endif
 649
 650         if (!quietlog) {
 651                 char *fname;
 652 #ifdef LOGIN_CAP
 653                 fname = login_getcapstr(lc, "copyright", NULL, NULL);
 654                 if (fname != NULL && access(fname, F_OK) == 0)
 655                         motd(fname);
 656                 else
 657 #endif
 658                         (void)printf("%s", copyrightstr);
 659
 660 #ifdef LOGIN_CAP
 661                 fname = login_getcapstr(lc, "welcome", NULL, NULL);
 662                 if (fname == NULL || access(fname, F_OK) != 0)
 663 #endif
 664                         fname = _PATH_MOTDFILE;
 665                 motd(fname);
 666
 667                 (void)snprintf(tbuf,
 668                     sizeof(tbuf), "%s/%s", _PATH_MAILDIR, pwd->pw_name);
 669                 if (stat(tbuf, &st) == 0 && st.st_size != 0)
 670                         (void)printf("You have %smail.\n",
 671                             (st.st_mtime > st.st_atime) ? "new " : "");
 672         }
 673
 674 #ifdef LOGIN_CAP
 675         login_close(lc);
 676 #endif
 677
 678         (void)signal(SIGALRM, SIG_DFL);
 679         (void)signal(SIGQUIT, SIG_DFL);
 680         (void)signal(SIGINT, SIG_DFL);
 681         (void)signal(SIGTSTP, SIG_IGN);
 682
 683         tbuf[0] = '-';
 684         (void)strlcpy(tbuf + 1, (p = strrchr(pwd->pw_shell, '/')) ?
 685             p + 1 : pwd->pw_shell, sizeof(tbuf) - 1);
 686
 687         /* Wait to change password until we're unprivileged */
 688         if (need_chpass) {
 689                 if (!require_chpass)
 690                         (void)printf(
 691 "Warning: your password has expired. Please change it as soon as possible.\n");
 692                 else {
 693                         int     status;
 694
 695                         (void)printf(
 696                     "Your password has expired. Please choose a new one.\n");
 697                         switch (fork()) {
 698                         case -1:
 699                                 warn("fork");
 700                                 sleepexit(EXIT_FAILURE);
 701                         case 0:
 702                                 execl(_PATH_BINPASSWD, "passwd", NULL);
 703                                 _exit(EXIT_FAILURE);
 704                         default:
 705                                 if (wait(&status) == -1 ||
 706                                     WEXITSTATUS(status))
 707                                         sleepexit(EXIT_FAILURE);
 708                         }
 709                 }
 710         }
 711
 712 #ifdef KERBEROS5
 713         if (login_krb5_get_tickets)
 714                 k5_write_creds();
 715 #endif
 716         execlp(pwd->pw_shell, tbuf, NULL);
 717         err(EXIT_FAILURE, "%s", pwd->pw_shell);
 718 }
 719
 720 #if defined(KERBEROS5)
 721 /*
 722  * This routine handles cleanup stuff, and the like.
 723  * It exists only in the child process.
 724  */
 725 static void
 726 dofork(void)
 727 {
 728         pid_t child, wchild;
 729
 730         switch (child = fork()) {
 731         case 0:
 732                 return; /* Child process */
 733         case -1:
 734                 err(EXIT_FAILURE, "Can't fork");
 735                 /*NOTREACHED*/
 736         default:
 737                 break;
 738         }
 739
 740         /*
 741          * Setup stuff?  This would be things we could do in parallel
 742          * with login
 743          */
 744         if (chdir("/") == -1)   /* Let's not keep the fs busy... */
 745                 err(EXIT_FAILURE, "Can't chdir to `/'");
 746
 747         /* If we're the parent, watch the child until it dies */
 748         while ((wchild = wait(NULL)) != child)
 749                 if (wchild == -1)
 750                         err(EXIT_FAILURE, "Can't wait");
 751
 752         /* Cleanup stuff */
 753         /* Run kdestroy to destroy tickets */
 754         if (login_krb5_get_tickets)
 755                 k5destroy();
 756
 757         /* Leave */
 758         exit(EXIT_SUCCESS);
 759 }
 760 #endif
 761
 762 static void
 763 checknologin(char *fname)
 764 {
 765         int fd, nchars;
 766         char tbuf[8192];
 767
 768         if ((fd = open(fname ? fname : _PATH_NOLOGIN, O_RDONLY, 0)) >= 0) {
 769                 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0)
 770                         (void)write(fileno(stdout), tbuf, nchars);
 771                 sleepexit(EXIT_SUCCESS);
 772         }
 773 }
 774
 775 static void
 776 usage(void)
 777 {
 778         (void)fprintf(stderr,
 779             "Usage: %s [-Ffps] [-a address] [-h hostname] [username]\n",
 780             getprogname());
 781         exit(EXIT_FAILURE);
 782 }