login.c revision 1.101
1 /* $NetBSD: login.c,v 1.101 2012/04/23 20:57:04 christos 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 1.101 2012/04/23 20:57:04 christos 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 <krb5/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(const 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 int notickets = 1; 122 extern krb5_context kcontext; 123 extern int have_forward; 124 extern char *krb5tkfile_env; 125 extern int krb5_configured; 126 #endif 127 128 static char *instance; 129 130 #if defined(KERBEROS5) 131 #define KERBEROS_CONFIGURED krb5_configured 132 #endif 133 134 extern char **environ; 135 136 int 137 main(int argc, char *argv[]) 138 { 139 struct group *gr; 140 struct stat st; 141 int ask, ch, cnt, fflag, hflag, pflag, sflag, quietlog, rootlogin, rval; 142 int Fflag; 143 uid_t uid, saved_uid; 144 gid_t saved_gid, saved_gids[NGROUPS_MAX]; 145 int nsaved_gids; 146 char *domain, *p, *ttyn; 147 const char *pwprompt; 148 char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10]; 149 char localhost[MAXHOSTNAMELEN + 1]; 150 int need_chpass, require_chpass; 151 int login_retries = DEFAULT_RETRIES, 152 login_backoff = DEFAULT_BACKOFF; 153 time_t pw_warntime = _PASSWORD_WARNDAYS * SECSPERDAY; 154 #ifdef KERBEROS5 155 krb5_error_code kerror; 156 #endif 157 #if defined(KERBEROS5) 158 int got_tickets = 0; 159 #endif 160 #ifdef LOGIN_CAP 161 char *shell = NULL; 162 login_cap_t *lc = NULL; 163 #endif 164 165 tbuf[0] = '\0'; 166 rval = 0; 167 pwprompt = NULL; 168 nested = NULL; 169 need_chpass = require_chpass = 0; 170 171 (void)signal(SIGALRM, timedout); 172 (void)alarm(timeout); 173 (void)signal(SIGQUIT, SIG_IGN); 174 (void)signal(SIGINT, SIG_IGN); 175 (void)setpriority(PRIO_PROCESS, 0, 0); 176 177 openlog("login", 0, LOG_AUTH); 178 179 /* 180 * -p is used by getty to tell login not to destroy the environment 181 * -f is used to skip a second login authentication 182 * -h is used by other servers to pass the name of the remote host to 183 * login so that it may be placed in utmp/utmpx and wtmp/wtmpx 184 * -a in addition to -h, a server may supply -a to pass the actual 185 * server address. 186 * -s is used to force use of S/Key or equivalent. 187 */ 188 domain = NULL; 189 if (gethostname(localhost, sizeof(localhost)) < 0) 190 syslog(LOG_ERR, "couldn't get local hostname: %m"); 191 else 192 domain = strchr(localhost, '.'); 193 localhost[sizeof(localhost) - 1] = '\0'; 194 195 Fflag = fflag = hflag = pflag = sflag = 0; 196 have_ss = 0; 197 #ifdef KERBEROS5 198 have_forward = 0; 199 #endif 200 uid = getuid(); 201 while ((ch = getopt(argc, argv, "a:Ffh:ps")) != -1) 202 switch (ch) { 203 case 'a': 204 if (uid) 205 errx(EXIT_FAILURE, "-a option: %s", strerror(EPERM)); 206 decode_ss(optarg); 207 #ifdef notdef 208 (void)sockaddr_snprintf(optarg, 209 sizeof(struct sockaddr_storage), "%a", (void *)&ss); 210 #endif 211 break; 212 case 'F': 213 Fflag = 1; 214 /* FALLTHROUGH */ 215 case 'f': 216 fflag = 1; 217 break; 218 case 'h': 219 if (uid) 220 errx(EXIT_FAILURE, "-h option: %s", strerror(EPERM)); 221 hflag = 1; 222 #ifdef notdef 223 if (domain && (p = strchr(optarg, '.')) != NULL && 224 strcasecmp(p, domain) == 0) 225 *p = '\0'; 226 #endif 227 hostname = optarg; 228 break; 229 case 'p': 230 pflag = 1; 231 break; 232 case 's': 233 sflag = 1; 234 break; 235 default: 236 case '?': 237 usage(); 238 break; 239 } 240 241 setproctitle(NULL); 242 argc -= optind; 243 argv += optind; 244 245 if (*argv) { 246 username = instance = *argv; 247 ask = 0; 248 } else 249 ask = 1; 250 251 #ifdef F_CLOSEM 252 (void)fcntl(3, F_CLOSEM, 0); 253 #else 254 for (cnt = getdtablesize(); cnt > 2; cnt--) 255 (void)close(cnt); 256 #endif 257 258 ttyn = ttyname(STDIN_FILENO); 259 if (ttyn == NULL || *ttyn == '\0') { 260 (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY); 261 ttyn = tname; 262 } 263 if ((tty = strstr(ttyn, "/pts/")) != NULL) 264 ++tty; 265 else if ((tty = strrchr(ttyn, '/')) != NULL) 266 ++tty; 267 else 268 tty = ttyn; 269 270 if (issetugid()) { 271 nested = strdup(user_from_uid(getuid(), 0)); 272 if (nested == NULL) { 273 syslog(LOG_ERR, "strdup: %m"); 274 sleepexit(EXIT_FAILURE); 275 } 276 } 277 278 #ifdef LOGIN_CAP 279 /* Get "login-retries" and "login-backoff" from default class */ 280 if ((lc = login_getclass(NULL)) != NULL) { 281 login_retries = (int)login_getcapnum(lc, "login-retries", 282 DEFAULT_RETRIES, DEFAULT_RETRIES); 283 login_backoff = (int)login_getcapnum(lc, "login-backoff", 284 DEFAULT_BACKOFF, DEFAULT_BACKOFF); 285 login_close(lc); 286 lc = NULL; 287 } 288 #endif 289 290 #ifdef KERBEROS5 291 kerror = krb5_init_context(&kcontext); 292 if (kerror) { 293 /* 294 * If Kerberos is not configured, that is, we are 295 * not using Kerberos, do not log the error message. 296 * However, if Kerberos is configured, and the 297 * context init fails for some other reason, we need 298 * to issue a no tickets warning to the user when the 299 * login succeeds. 300 */ 301 if (kerror != ENXIO) { /* XXX NetBSD-local Heimdal hack */ 302 syslog(LOG_NOTICE, 303 "%s when initializing Kerberos context", 304 error_message(kerror)); 305 krb5_configured = 1; 306 } 307 login_krb5_get_tickets = 0; 308 } 309 #endif /* KERBEROS5 */ 310 311 for (cnt = 0;; ask = 1) { 312 char *ptr; 313 #if defined(KERBEROS5) 314 if (login_krb5_get_tickets) 315 k5destroy(); 316 #endif 317 if (ask) { 318 fflag = 0; 319 instance = getloginname(); 320 } 321 rootlogin = 0; 322 ptr = instance; 323 #ifdef KERBEROS5 324 if ((instance = strchr(instance, '/')) != NULL) 325 *instance++ = '\0'; 326 else 327 instance = __UNCONST(""); 328 #endif 329 username = trimloginname(ptr); 330 /* 331 * Note if trying multiple user names; log failures for 332 * previous user name, but don't bother logging one failure 333 * for nonexistent name (mistyped username). 334 */ 335 if (failures && strcmp(tbuf, username)) { 336 if (failures > (pwd ? 0 : 1)) 337 badlogin(tbuf); 338 failures = 0; 339 } 340 (void)strlcpy(tbuf, username, sizeof(tbuf)); 341 342 pwd = getpwnam(username); 343 344 #ifdef LOGIN_CAP 345 /* 346 * Establish the class now, before we might goto 347 * within the next block. pwd can be NULL since it 348 * falls back to the "default" class if it is. 349 */ 350 lc = login_getclass(pwd ? pwd->pw_class : NULL); 351 #endif 352 /* 353 * if we have a valid account name, and it doesn't have a 354 * password, or the -f option was specified and the caller 355 * is root or the caller isn't changing their uid, don't 356 * authenticate. 357 */ 358 if (pwd) { 359 if (pwd->pw_uid == 0) 360 rootlogin = 1; 361 362 if (fflag && (uid == 0 || uid == pwd->pw_uid)) { 363 /* already authenticated */ 364 #ifdef KERBEROS5 365 if (login_krb5_get_tickets && Fflag) 366 k5_read_creds(username); 367 #endif 368 break; 369 } else if (pwd->pw_passwd[0] == '\0') { 370 /* pretend password okay */ 371 rval = 0; 372 goto ttycheck; 373 } 374 } 375 376 fflag = 0; 377 378 (void)setpriority(PRIO_PROCESS, 0, -4); 379 380 #ifdef SKEY 381 if (skey_haskey(username) == 0) { 382 static char skprompt[80]; 383 const char *skinfo = skey_keyinfo(username); 384 385 (void)snprintf(skprompt, sizeof(skprompt), 386 "Password [ %s ]:", 387 skinfo ? skinfo : "error getting challenge"); 388 pwprompt = skprompt; 389 } else 390 #endif 391 pwprompt = "Password:"; 392 393 p = getpass(pwprompt); 394 395 if (pwd == NULL) { 396 rval = 1; 397 goto skip; 398 } 399 #ifdef KERBEROS5 400 if (login_krb5_get_tickets && 401 k5login(pwd, instance, localhost, p) == 0) { 402 rval = 0; 403 got_tickets = 1; 404 } 405 #endif 406 #if defined(KERBEROS5) 407 if (got_tickets) 408 goto skip; 409 #endif 410 #ifdef SKEY 411 if (skey_haskey(username) == 0 && 412 skey_passcheck(username, p) != -1) { 413 rval = 0; 414 goto skip; 415 } 416 #endif 417 if (!sflag && *pwd->pw_passwd != '\0' && 418 !strcmp(crypt(p, pwd->pw_passwd), pwd->pw_passwd)) { 419 rval = 0; 420 require_chpass = 1; 421 goto skip; 422 } 423 rval = 1; 424 425 skip: 426 memset(p, 0, strlen(p)); 427 428 (void)setpriority(PRIO_PROCESS, 0, 0); 429 430 ttycheck: 431 /* 432 * If trying to log in as root without Kerberos, 433 * but with insecure terminal, refuse the login attempt. 434 */ 435 if (pwd && !rval && rootlogin && !rootterm(tty)) { 436 (void)printf("Login incorrect or refused on this " 437 "terminal.\n"); 438 if (hostname) 439 syslog(LOG_NOTICE, 440 "LOGIN %s REFUSED FROM %s ON TTY %s", 441 pwd->pw_name, hostname, tty); 442 else 443 syslog(LOG_NOTICE, 444 "LOGIN %s REFUSED ON TTY %s", 445 pwd->pw_name, tty); 446 continue; 447 } 448 449 if (pwd && !rval) 450 break; 451 452 (void)printf("Login incorrect or refused on this " 453 "terminal.\n"); 454 failures++; 455 cnt++; 456 /* 457 * We allow login_retries tries, but after login_backoff 458 * we start backing off. These default to 10 and 3 459 * respectively. 460 */ 461 if (cnt > login_backoff) { 462 if (cnt >= login_retries) { 463 badlogin(username); 464 sleepexit(EXIT_FAILURE); 465 } 466 sleep((u_int)((cnt - login_backoff) * 5)); 467 } 468 } 469 470 /* committed to login -- turn off timeout */ 471 (void)alarm((u_int)0); 472 473 endpwent(); 474 475 /* if user not super-user, check for disabled logins */ 476 #ifdef LOGIN_CAP 477 if (!login_getcapbool(lc, "ignorenologin", rootlogin)) 478 checknologin(login_getcapstr(lc, "nologin", NULL, NULL)); 479 #else 480 if (!rootlogin) 481 checknologin(NULL); 482 #endif 483 484 #ifdef LOGIN_CAP 485 quietlog = login_getcapbool(lc, "hushlogin", 0); 486 #else 487 quietlog = 0; 488 #endif 489 /* Temporarily give up special privileges so we can change */ 490 /* into NFS-mounted homes that are exported for non-root */ 491 /* access and have mode 7x0 */ 492 saved_uid = geteuid(); 493 saved_gid = getegid(); 494 nsaved_gids = getgroups(NGROUPS_MAX, saved_gids); 495 496 (void)setegid(pwd->pw_gid); 497 initgroups(username, pwd->pw_gid); 498 (void)seteuid(pwd->pw_uid); 499 500 if (chdir(pwd->pw_dir) < 0) { 501 #ifdef LOGIN_CAP 502 if (login_getcapbool(lc, "requirehome", 0)) { 503 (void)printf("Home directory %s required\n", 504 pwd->pw_dir); 505 sleepexit(EXIT_FAILURE); 506 } 507 #endif 508 (void)printf("No home directory %s!\n", pwd->pw_dir); 509 if (chdir("/") == -1) 510 exit(EXIT_FAILURE); 511 pwd->pw_dir = __UNCONST("/"); 512 (void)printf("Logging in with home = \"/\".\n"); 513 } 514 515 if (!quietlog) 516 quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0; 517 518 /* regain special privileges */ 519 (void)seteuid(saved_uid); 520 setgroups(nsaved_gids, saved_gids); 521 (void)setegid(saved_gid); 522 523 #ifdef LOGIN_CAP 524 pw_warntime = login_getcaptime(lc, "password-warn", 525 _PASSWORD_WARNDAYS * SECSPERDAY, 526 _PASSWORD_WARNDAYS * SECSPERDAY); 527 #endif 528 529 (void)gettimeofday(&now, NULL); 530 if (pwd->pw_expire) { 531 if (now.tv_sec >= pwd->pw_expire) { 532 (void)printf("Sorry -- your account has expired.\n"); 533 sleepexit(EXIT_FAILURE); 534 } else if (pwd->pw_expire - now.tv_sec < pw_warntime && 535 !quietlog) 536 (void)printf("Warning: your account expires on %s", 537 ctime(&pwd->pw_expire)); 538 } 539 if (pwd->pw_change) { 540 if (pwd->pw_change == _PASSWORD_CHGNOW) 541 need_chpass = 1; 542 else if (now.tv_sec >= pwd->pw_change) { 543 (void)printf("Sorry -- your password has expired.\n"); 544 sleepexit(EXIT_FAILURE); 545 } else if (pwd->pw_change - now.tv_sec < pw_warntime && 546 !quietlog) 547 (void)printf("Warning: your password expires on %s", 548 ctime(&pwd->pw_change)); 549 550 } 551 /* Nothing else left to fail -- really log in. */ 552 update_db(quietlog, rootlogin, fflag); 553 554 (void)chown(ttyn, pwd->pw_uid, 555 (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid); 556 557 if (ttyaction(ttyn, "login", pwd->pw_name)) 558 (void)printf("Warning: ttyaction failed.\n"); 559 560 #if defined(KERBEROS5) 561 /* Fork so that we can call kdestroy */ 562 if (! login_krb5_retain_ccache && has_ccache) 563 dofork(); 564 #endif 565 566 /* Destroy environment unless user has requested its preservation. */ 567 if (!pflag) 568 environ = envinit; 569 570 #ifdef LOGIN_CAP 571 if (nested == NULL && setusercontext(lc, pwd, pwd->pw_uid, 572 LOGIN_SETLOGIN) != 0) { 573 syslog(LOG_ERR, "setusercontext failed"); 574 exit(EXIT_FAILURE); 575 } 576 if (setusercontext(lc, pwd, pwd->pw_uid, 577 (LOGIN_SETALL & ~(LOGIN_SETPATH|LOGIN_SETLOGIN))) != 0) { 578 syslog(LOG_ERR, "setusercontext failed"); 579 exit(EXIT_FAILURE); 580 } 581 #else 582 (void)setgid(pwd->pw_gid); 583 584 initgroups(username, pwd->pw_gid); 585 586 if (nested == NULL && setlogin(pwd->pw_name) < 0) 587 syslog(LOG_ERR, "setlogin() failure: %m"); 588 589 /* Discard permissions last so can't get killed and drop core. */ 590 if (rootlogin) 591 (void)setuid(0); 592 else 593 (void)setuid(pwd->pw_uid); 594 #endif 595 596 if (*pwd->pw_shell == '\0') 597 pwd->pw_shell = __UNCONST(_PATH_BSHELL); 598 #ifdef LOGIN_CAP 599 if ((shell = login_getcapstr(lc, "shell", NULL, NULL)) != NULL) { 600 if ((shell = strdup(shell)) == NULL) { 601 syslog(LOG_ERR, "Cannot alloc mem"); 602 sleepexit(EXIT_FAILURE); 603 } 604 pwd->pw_shell = shell; 605 } 606 #endif 607 608 (void)setenv("HOME", pwd->pw_dir, 1); 609 (void)setenv("SHELL", pwd->pw_shell, 1); 610 if (term[0] == '\0') { 611 const char *tt = stypeof(tty); 612 #ifdef LOGIN_CAP 613 if (tt == NULL) 614 tt = login_getcapstr(lc, "term", NULL, NULL); 615 #endif 616 /* unknown term -> "su" */ 617 (void)strlcpy(term, tt != NULL ? tt : "su", sizeof(term)); 618 } 619 (void)setenv("TERM", term, 0); 620 (void)setenv("LOGNAME", pwd->pw_name, 1); 621 (void)setenv("USER", pwd->pw_name, 1); 622 623 #ifdef LOGIN_CAP 624 setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETPATH); 625 #else 626 (void)setenv("PATH", _PATH_DEFPATH, 0); 627 #endif 628 629 #ifdef KERBEROS5 630 if (krb5tkfile_env) 631 (void)setenv("KRB5CCNAME", krb5tkfile_env, 1); 632 #endif 633 634 if (tty[sizeof("tty")-1] == 'd') 635 syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name); 636 637 /* If fflag is on, assume caller/authenticator has logged root login. */ 638 if (rootlogin && fflag == 0) { 639 if (hostname) 640 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s", 641 username, tty, hostname); 642 else 643 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s", 644 username, tty); 645 } 646 647 #if defined(KERBEROS5) 648 if (KERBEROS_CONFIGURED && !quietlog && notickets == 1) 649 (void)printf("Warning: no Kerberos tickets issued.\n"); 650 #endif 651 652 if (!quietlog) { 653 const char *fname; 654 #ifdef LOGIN_CAP 655 fname = login_getcapstr(lc, "copyright", NULL, NULL); 656 if (fname != NULL && access(fname, F_OK) == 0) 657 motd(fname); 658 else 659 #endif 660 (void)printf("%s", copyrightstr); 661 662 #ifdef LOGIN_CAP 663 fname = login_getcapstr(lc, "welcome", NULL, NULL); 664 if (fname == NULL || access(fname, F_OK) != 0) 665 #endif 666 fname = _PATH_MOTDFILE; 667 motd(fname); 668 669 (void)snprintf(tbuf, 670 sizeof(tbuf), "%s/%s", _PATH_MAILDIR, pwd->pw_name); 671 if (stat(tbuf, &st) == 0 && st.st_size != 0) 672 (void)printf("You have %smail.\n", 673 (st.st_mtime > st.st_atime) ? "new " : ""); 674 } 675 676 #ifdef LOGIN_CAP 677 login_close(lc); 678 #endif 679 680 (void)signal(SIGALRM, SIG_DFL); 681 (void)signal(SIGQUIT, SIG_DFL); 682 (void)signal(SIGINT, SIG_DFL); 683 (void)signal(SIGTSTP, SIG_IGN); 684 685 tbuf[0] = '-'; 686 (void)strlcpy(tbuf + 1, (p = strrchr(pwd->pw_shell, '/')) ? 687 p + 1 : pwd->pw_shell, sizeof(tbuf) - 1); 688 689 /* Wait to change password until we're unprivileged */ 690 if (need_chpass) { 691 if (!require_chpass) 692 (void)printf( 693 "Warning: your password has expired. Please change it as soon as possible.\n"); 694 else { 695 int status; 696 697 (void)printf( 698 "Your password has expired. Please choose a new one.\n"); 699 switch (fork()) { 700 case -1: 701 warn("fork"); 702 sleepexit(EXIT_FAILURE); 703 case 0: 704 execl(_PATH_BINPASSWD, "passwd", NULL); 705 _exit(EXIT_FAILURE); 706 default: 707 if (wait(&status) == -1 || 708 WEXITSTATUS(status)) 709 sleepexit(EXIT_FAILURE); 710 } 711 } 712 } 713 714 #ifdef KERBEROS5 715 if (login_krb5_get_tickets) 716 k5_write_creds(); 717 #endif 718 execlp(pwd->pw_shell, tbuf, NULL); 719 err(EXIT_FAILURE, "%s", pwd->pw_shell); 720 } 721 722 #if defined(KERBEROS5) 723 /* 724 * This routine handles cleanup stuff, and the like. 725 * It exists only in the child process. 726 */ 727 static void 728 dofork(void) 729 { 730 pid_t child, wchild; 731 732 switch (child = fork()) { 733 case 0: 734 return; /* Child process */ 735 case -1: 736 err(EXIT_FAILURE, "Can't fork"); 737 /*NOTREACHED*/ 738 default: 739 break; 740 } 741 742 /* 743 * Setup stuff? This would be things we could do in parallel 744 * with login 745 */ 746 if (chdir("/") == -1) /* Let's not keep the fs busy... */ 747 err(EXIT_FAILURE, "Can't chdir to `/'"); 748 749 /* If we're the parent, watch the child until it dies */ 750 while ((wchild = wait(NULL)) != child) 751 if (wchild == -1) 752 err(EXIT_FAILURE, "Can't wait"); 753 754 /* Cleanup stuff */ 755 /* Run kdestroy to destroy tickets */ 756 if (login_krb5_get_tickets) 757 k5destroy(); 758 759 /* Leave */ 760 exit(EXIT_SUCCESS); 761 } 762 #endif 763 764 static void 765 checknologin(char *fname) 766 { 767 int fd, nchars; 768 char tbuf[8192]; 769 770 if ((fd = open(fname ? fname : _PATH_NOLOGIN, O_RDONLY, 0)) >= 0) { 771 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0) 772 (void)write(fileno(stdout), tbuf, nchars); 773 sleepexit(EXIT_SUCCESS); 774 } 775 } 776 777 static void 778 usage(void) 779 { 780 (void)fprintf(stderr, 781 "Usage: %s [-Ffps] [-a address] [-h hostname] [username]\n", 782 getprogname()); 783 exit(EXIT_FAILURE); 784 } 785
Indexes created Wed Oct 01 07:09:59 GMT 2025