login.c revision 1.99
1 /* $NetBSD: login.c,v 1.99 2012/04/22 23:26:19 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 1.99 2012/04/22 23:26:19 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 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; 146 const char *pwprompt; 147 char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10]; 148 char localhost[MAXHOSTNAMELEN + 1]; 149 int need_chpass, require_chpass; 150 int login_retries = DEFAULT_RETRIES, 151 login_backoff = DEFAULT_BACKOFF; 152 time_t pw_warntime = _PASSWORD_WARNDAYS * SECSPERDAY; 153 #ifdef KERBEROS5 154 krb5_error_code kerror; 155 #endif 156 #if defined(KERBEROS5) 157 int got_tickets = 0; 158 #endif 159 #ifdef LOGIN_CAP 160 char *shell = NULL; 161 login_cap_t *lc = NULL; 162 #endif 163 164 tbuf[0] = '\0'; 165 rval = 0; 166 pwprompt = NULL; 167 nested = NULL; 168 need_chpass = require_chpass = 0; 169 170 (void)signal(SIGALRM, timedout); 171 (void)alarm(timeout); 172 (void)signal(SIGQUIT, SIG_IGN); 173 (void)signal(SIGINT, SIG_IGN); 174 (void)setpriority(PRIO_PROCESS, 0, 0); 175 176 openlog("login", 0, LOG_AUTH); 177 178 /* 179 * -p is used by getty to tell login not to destroy the environment 180 * -f is used to skip a second login authentication 181 * -h is used by other servers to pass the name of the remote host to 182 * login so that it may be placed in utmp/utmpx and wtmp/wtmpx 183 * -a in addition to -h, a server may supply -a to pass the actual 184 * server address. 185 * -s is used to force use of S/Key or equivalent. 186 */ 187 domain = NULL; 188 if (gethostname(localhost, sizeof(localhost)) < 0) 189 syslog(LOG_ERR, "couldn't get local hostname: %m"); 190 else 191 domain = strchr(localhost, '.'); 192 localhost[sizeof(localhost) - 1] = '\0'; 193 194 Fflag = fflag = hflag = pflag = sflag = 0; 195 have_ss = 0; 196 #ifdef KERBEROS5 197 have_forward = 0; 198 #endif 199 uid = getuid(); 200 while ((ch = getopt(argc, argv, "a:Ffh:ps")) != -1) 201 switch (ch) { 202 case 'a': 203 if (uid) 204 errx(EXIT_FAILURE, "-a option: %s", strerror(EPERM)); 205 decode_ss(optarg); 206 #ifdef notdef 207 (void)sockaddr_snprintf(optarg, 208 sizeof(struct sockaddr_storage), "%a", (void *)&ss); 209 #endif 210 break; 211 case 'F': 212 Fflag = 1; 213 /* FALLTHROUGH */ 214 case 'f': 215 fflag = 1; 216 break; 217 case 'h': 218 if (uid) 219 errx(EXIT_FAILURE, "-h option: %s", strerror(EPERM)); 220 hflag = 1; 221 #ifdef notdef 222 if (domain && (p = strchr(optarg, '.')) != NULL && 223 strcasecmp(p, domain) == 0) 224 *p = '\0'; 225 #endif 226 hostname = optarg; 227 break; 228 case 'p': 229 pflag = 1; 230 break; 231 case 's': 232 sflag = 1; 233 break; 234 default: 235 case '?': 236 usage(); 237 break; 238 } 239 240 setproctitle(NULL); 241 argc -= optind; 242 argv += optind; 243 244 if (*argv) { 245 username = instance = *argv; 246 ask = 0; 247 } else 248 ask = 1; 249 250 #ifdef F_CLOSEM 251 (void)fcntl(3, F_CLOSEM, 0); 252 #else 253 for (cnt = getdtablesize(); cnt > 2; cnt--) 254 (void)close(cnt); 255 #endif 256 257 ttyn = ttyname(STDIN_FILENO); 258 if (ttyn == NULL || *ttyn == '\0') { 259 (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY); 260 ttyn = tname; 261 } 262 if ((tty = strstr(ttyn, "/pts/")) != NULL) 263 ++tty; 264 else if ((tty = strrchr(ttyn, '/')) != NULL) 265 ++tty; 266 else 267 tty = ttyn; 268 269 if (issetugid()) { 270 nested = strdup(user_from_uid(getuid(), 0)); 271 if (nested == NULL) { 272 syslog(LOG_ERR, "strdup: %m"); 273 sleepexit(EXIT_FAILURE); 274 } 275 } 276 277 #ifdef LOGIN_CAP 278 /* Get "login-retries" and "login-backoff" from default class */ 279 if ((lc = login_getclass(NULL)) != NULL) { 280 login_retries = (int)login_getcapnum(lc, "login-retries", 281 DEFAULT_RETRIES, DEFAULT_RETRIES); 282 login_backoff = (int)login_getcapnum(lc, "login-backoff", 283 DEFAULT_BACKOFF, DEFAULT_BACKOFF); 284 login_close(lc); 285 lc = NULL; 286 } 287 #endif 288 289 #ifdef KERBEROS5 290 kerror = krb5_init_context(&kcontext); 291 if (kerror) { 292 /* 293 * If Kerberos is not configured, that is, we are 294 * not using Kerberos, do not log the error message. 295 * However, if Kerberos is configured, and the 296 * context init fails for some other reason, we need 297 * to issue a no tickets warning to the user when the 298 * login succeeds. 299 */ 300 if (kerror != ENXIO) { /* XXX NetBSD-local Heimdal hack */ 301 syslog(LOG_NOTICE, 302 "%s when initializing Kerberos context", 303 error_message(kerror)); 304 krb5_configured = 1; 305 } 306 login_krb5_get_tickets = 0; 307 } 308 #endif /* KERBEROS5 */ 309 310 for (cnt = 0;; ask = 1) { 311 char *ptr; 312 #if defined(KERBEROS5) 313 if (login_krb5_get_tickets) 314 k5destroy(); 315 #endif 316 if (ask) { 317 fflag = 0; 318 instance = getloginname(); 319 } 320 rootlogin = 0; 321 ptr = instance; 322 #ifdef KERBEROS5 323 if ((instance = strchr(instance, '/')) != NULL) 324 *instance++ = '\0'; 325 else 326 instance = __UNCONST(""); 327 #endif 328 username = trimloginname(ptr); 329 /* 330 * Note if trying multiple user names; log failures for 331 * previous user name, but don't bother logging one failure 332 * for nonexistent name (mistyped username). 333 */ 334 if (failures && strcmp(tbuf, username)) { 335 if (failures > (pwd ? 0 : 1)) 336 badlogin(tbuf); 337 failures = 0; 338 } 339 (void)strlcpy(tbuf, username, sizeof(tbuf)); 340 341 pwd = getpwnam(username); 342 343 #ifdef LOGIN_CAP 344 /* 345 * Establish the class now, before we might goto 346 * within the next block. pwd can be NULL since it 347 * falls back to the "default" class if it is. 348 */ 349 lc = login_getclass(pwd ? pwd->pw_class : NULL); 350 #endif 351 /* 352 * if we have a valid account name, and it doesn't have a 353 * password, or the -f option was specified and the caller 354 * is root or the caller isn't changing their uid, don't 355 * authenticate. 356 */ 357 if (pwd) { 358 if (pwd->pw_uid == 0) 359 rootlogin = 1; 360 361 if (fflag && (uid == 0 || uid == pwd->pw_uid)) { 362 /* already authenticated */ 363 #ifdef KERBEROS5 364 if (login_krb5_get_tickets && Fflag) 365 k5_read_creds(username); 366 #endif 367 break; 368 } else if (pwd->pw_passwd[0] == '\0') { 369 /* pretend password okay */ 370 rval = 0; 371 goto ttycheck; 372 } 373 } 374 375 fflag = 0; 376 377 (void)setpriority(PRIO_PROCESS, 0, -4); 378 379 #ifdef SKEY 380 if (skey_haskey(username) == 0) { 381 static char skprompt[80]; 382 const char *skinfo = skey_keyinfo(username); 383 384 (void)snprintf(skprompt, sizeof(skprompt), 385 "Password [ %s ]:", 386 skinfo ? skinfo : "error getting challenge"); 387 pwprompt = skprompt; 388 } else 389 #endif 390 pwprompt = "Password:"; 391 392 p = getpass(pwprompt); 393 394 if (pwd == NULL) { 395 rval = 1; 396 goto skip; 397 } 398 #ifdef KERBEROS5 399 if (login_krb5_get_tickets && 400 k5login(pwd, instance, localhost, p) == 0) { 401 rval = 0; 402 got_tickets = 1; 403 } 404 #endif 405 #if defined(KERBEROS5) 406 if (got_tickets) 407 goto skip; 408 #endif 409 #ifdef SKEY 410 if (skey_haskey(username) == 0 && 411 skey_passcheck(username, p) != -1) { 412 rval = 0; 413 goto skip; 414 } 415 #endif 416 if (!sflag && *pwd->pw_passwd != '\0' && 417 !strcmp(crypt(p, pwd->pw_passwd), pwd->pw_passwd)) { 418 rval = 0; 419 require_chpass = 1; 420 goto skip; 421 } 422 rval = 1; 423 424 skip: 425 memset(p, 0, strlen(p)); 426 427 (void)setpriority(PRIO_PROCESS, 0, 0); 428 429 ttycheck: 430 /* 431 * If trying to log in as root without Kerberos, 432 * but with insecure terminal, refuse the login attempt. 433 */ 434 if (pwd && !rval && rootlogin && !rootterm(tty)) { 435 (void)printf("Login incorrect or refused on this " 436 "terminal.\n"); 437 if (hostname) 438 syslog(LOG_NOTICE, 439 "LOGIN %s REFUSED FROM %s ON TTY %s", 440 pwd->pw_name, hostname, tty); 441 else 442 syslog(LOG_NOTICE, 443 "LOGIN %s REFUSED ON TTY %s", 444 pwd->pw_name, tty); 445 continue; 446 } 447 448 if (pwd && !rval) 449 break; 450 451 (void)printf("Login incorrect or refused on this " 452 "terminal.\n"); 453 failures++; 454 cnt++; 455 /* 456 * We allow login_retries tries, but after login_backoff 457 * we start backing off. These default to 10 and 3 458 * respectively. 459 */ 460 if (cnt > login_backoff) { 461 if (cnt >= login_retries) { 462 badlogin(username); 463 sleepexit(EXIT_FAILURE); 464 } 465 sleep((u_int)((cnt - login_backoff) * 5)); 466 } 467 } 468 469 /* committed to login -- turn off timeout */ 470 (void)alarm((u_int)0); 471 472 endpwent(); 473 474 /* if user not super-user, check for disabled logins */ 475 #ifdef LOGIN_CAP 476 if (!login_getcapbool(lc, "ignorenologin", rootlogin)) 477 checknologin(login_getcapstr(lc, "nologin", NULL, NULL)); 478 #else 479 if (!rootlogin) 480 checknologin(NULL); 481 #endif 482 483 #ifdef LOGIN_CAP 484 quietlog = login_getcapbool(lc, "hushlogin", 0); 485 #else 486 quietlog = 0; 487 #endif 488 /* Temporarily give up special privileges so we can change */ 489 /* into NFS-mounted homes that are exported for non-root */ 490 /* access and have mode 7x0 */ 491 saved_uid = geteuid(); 492 saved_gid = getegid(); 493 nsaved_gids = getgroups(NGROUPS_MAX, saved_gids); 494 495 (void)setegid(pwd->pw_gid); 496 initgroups(username, pwd->pw_gid); 497 (void)seteuid(pwd->pw_uid); 498 499 if (chdir(pwd->pw_dir) < 0) { 500 #ifdef LOGIN_CAP 501 if (login_getcapbool(lc, "requirehome", 0)) { 502 (void)printf("Home directory %s required\n", 503 pwd->pw_dir); 504 sleepexit(EXIT_FAILURE); 505 } 506 #endif 507 (void)printf("No home directory %s!\n", pwd->pw_dir); 508 if (chdir("/") == -1) 509 exit(EXIT_FAILURE); 510 pwd->pw_dir = __UNCONST("/"); 511 (void)printf("Logging in with home = \"/\".\n"); 512 } 513 514 if (!quietlog) 515 quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0; 516 517 /* regain special privileges */ 518 (void)seteuid(saved_uid); 519 setgroups(nsaved_gids, saved_gids); 520 (void)setegid(saved_gid); 521 522 #ifdef LOGIN_CAP 523 pw_warntime = login_getcaptime(lc, "password-warn", 524 _PASSWORD_WARNDAYS * SECSPERDAY, 525 _PASSWORD_WARNDAYS * SECSPERDAY); 526 #endif 527 528 (void)gettimeofday(&now, NULL); 529 if (pwd->pw_expire) { 530 if (now.tv_sec >= pwd->pw_expire) { 531 (void)printf("Sorry -- your account has expired.\n"); 532 sleepexit(EXIT_FAILURE); 533 } else if (pwd->pw_expire - now.tv_sec < pw_warntime && 534 !quietlog) 535 (void)printf("Warning: your account expires on %s", 536 ctime(&pwd->pw_expire)); 537 } 538 if (pwd->pw_change) { 539 if (pwd->pw_change == _PASSWORD_CHGNOW) 540 need_chpass = 1; 541 else if (now.tv_sec >= pwd->pw_change) { 542 (void)printf("Sorry -- your password has expired.\n"); 543 sleepexit(EXIT_FAILURE); 544 } else if (pwd->pw_change - now.tv_sec < pw_warntime && 545 !quietlog) 546 (void)printf("Warning: your password expires on %s", 547 ctime(&pwd->pw_change)); 548 549 } 550 /* Nothing else left to fail -- really log in. */ 551 update_db(quietlog, rootlogin, fflag); 552 553 (void)chown(ttyn, pwd->pw_uid, 554 (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid); 555 556 if (ttyaction(ttyn, "login", pwd->pw_name)) 557 (void)printf("Warning: ttyaction failed.\n"); 558 559 #if defined(KERBEROS5) 560 /* Fork so that we can call kdestroy */ 561 if (! login_krb5_retain_ccache && has_ccache) 562 dofork(); 563 #endif 564 565 /* Destroy environment unless user has requested its preservation. */ 566 if (!pflag) 567 environ = envinit; 568 569 #ifdef LOGIN_CAP 570 if (nested == NULL && setusercontext(lc, pwd, pwd->pw_uid, 571 LOGIN_SETLOGIN) != 0) { 572 syslog(LOG_ERR, "setusercontext failed"); 573 exit(EXIT_FAILURE); 574 } 575 if (setusercontext(lc, pwd, pwd->pw_uid, 576 (LOGIN_SETALL & ~(LOGIN_SETPATH|LOGIN_SETLOGIN))) != 0) { 577 syslog(LOG_ERR, "setusercontext failed"); 578 exit(EXIT_FAILURE); 579 } 580 #else 581 (void)setgid(pwd->pw_gid); 582 583 initgroups(username, pwd->pw_gid); 584 585 if (nested == NULL && setlogin(pwd->pw_name) < 0) 586 syslog(LOG_ERR, "setlogin() failure: %m"); 587 588 /* Discard permissions last so can't get killed and drop core. */ 589 if (rootlogin) 590 (void)setuid(0); 591 else 592 (void)setuid(pwd->pw_uid); 593 #endif 594 595 if (*pwd->pw_shell == '\0') 596 pwd->pw_shell = __UNCONST(_PATH_BSHELL); 597 #ifdef LOGIN_CAP 598 if ((shell = login_getcapstr(lc, "shell", NULL, NULL)) != NULL) { 599 if ((shell = strdup(shell)) == NULL) { 600 syslog(LOG_ERR, "Cannot alloc mem"); 601 sleepexit(EXIT_FAILURE); 602 } 603 pwd->pw_shell = shell; 604 } 605 #endif 606 607 (void)setenv("HOME", pwd->pw_dir, 1); 608 (void)setenv("SHELL", pwd->pw_shell, 1); 609 if (term[0] == '\0') { 610 const char *tt = stypeof(tty); 611 #ifdef LOGIN_CAP 612 if (tt == NULL) 613 tt = login_getcapstr(lc, "term", NULL, NULL); 614 #endif 615 /* unknown term -> "su" */ 616 (void)strlcpy(term, tt != NULL ? tt : "su", sizeof(term)); 617 } 618 (void)setenv("TERM", term, 0); 619 (void)setenv("LOGNAME", pwd->pw_name, 1); 620 (void)setenv("USER", pwd->pw_name, 1); 621 622 #ifdef LOGIN_CAP 623 setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETPATH); 624 #else 625 (void)setenv("PATH", _PATH_DEFPATH, 0); 626 #endif 627 628 #ifdef KERBEROS5 629 if (krb5tkfile_env) 630 (void)setenv("KRB5CCNAME", krb5tkfile_env, 1); 631 #endif 632 633 if (tty[sizeof("tty")-1] == 'd') 634 syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name); 635 636 /* If fflag is on, assume caller/authenticator has logged root login. */ 637 if (rootlogin && fflag == 0) { 638 if (hostname) 639 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s", 640 username, tty, hostname); 641 else 642 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s", 643 username, tty); 644 } 645 646 #if defined(KERBEROS5) 647 if (KERBEROS_CONFIGURED && !quietlog && notickets == 1) 648 (void)printf("Warning: no Kerberos tickets issued.\n"); 649 #endif 650 651 if (!quietlog) { 652 const char *fname; 653 #ifdef LOGIN_CAP 654 fname = login_getcapstr(lc, "copyright", NULL, NULL); 655 if (fname != NULL && access(fname, F_OK) == 0) 656 motd(fname); 657 else 658 #endif 659 (void)printf("%s", copyrightstr); 660 661 #ifdef LOGIN_CAP 662 fname = login_getcapstr(lc, "welcome", NULL, NULL); 663 if (fname == NULL || access(fname, F_OK) != 0) 664 #endif 665 fname = _PATH_MOTDFILE; 666 motd(fname); 667 668 (void)snprintf(tbuf, 669 sizeof(tbuf), "%s/%s", _PATH_MAILDIR, pwd->pw_name); 670 if (stat(tbuf, &st) == 0 && st.st_size != 0) 671 (void)printf("You have %smail.\n", 672 (st.st_mtime > st.st_atime) ? "new " : ""); 673 } 674 675 #ifdef LOGIN_CAP 676 login_close(lc); 677 #endif 678 679 (void)signal(SIGALRM, SIG_DFL); 680 (void)signal(SIGQUIT, SIG_DFL); 681 (void)signal(SIGINT, SIG_DFL); 682 (void)signal(SIGTSTP, SIG_IGN); 683 684 tbuf[0] = '-'; 685 (void)strlcpy(tbuf + 1, (p = strrchr(pwd->pw_shell, '/')) ? 686 p + 1 : pwd->pw_shell, sizeof(tbuf) - 1); 687 688 /* Wait to change password until we're unprivileged */ 689 if (need_chpass) { 690 if (!require_chpass) 691 (void)printf( 692 "Warning: your password has expired. Please change it as soon as possible.\n"); 693 else { 694 int status; 695 696 (void)printf( 697 "Your password has expired. Please choose a new one.\n"); 698 switch (fork()) { 699 case -1: 700 warn("fork"); 701 sleepexit(EXIT_FAILURE); 702 case 0: 703 execl(_PATH_BINPASSWD, "passwd", NULL); 704 _exit(EXIT_FAILURE); 705 default: 706 if (wait(&status) == -1 || 707 WEXITSTATUS(status)) 708 sleepexit(EXIT_FAILURE); 709 } 710 } 711 } 712 713 #ifdef KERBEROS5 714 if (login_krb5_get_tickets) 715 k5_write_creds(); 716 #endif 717 execlp(pwd->pw_shell, tbuf, NULL); 718 err(EXIT_FAILURE, "%s", pwd->pw_shell); 719 } 720 721 #if defined(KERBEROS5) 722 /* 723 * This routine handles cleanup stuff, and the like. 724 * It exists only in the child process. 725 */ 726 static void 727 dofork(void) 728 { 729 pid_t child, wchild; 730 731 switch (child = fork()) { 732 case 0: 733 return; /* Child process */ 734 case -1: 735 err(EXIT_FAILURE, "Can't fork"); 736 /*NOTREACHED*/ 737 default: 738 break; 739 } 740 741 /* 742 * Setup stuff? This would be things we could do in parallel 743 * with login 744 */ 745 if (chdir("/") == -1) /* Let's not keep the fs busy... */ 746 err(EXIT_FAILURE, "Can't chdir to `/'"); 747 748 /* If we're the parent, watch the child until it dies */ 749 while ((wchild = wait(NULL)) != child) 750 if (wchild == -1) 751 err(EXIT_FAILURE, "Can't wait"); 752 753 /* Cleanup stuff */ 754 /* Run kdestroy to destroy tickets */ 755 if (login_krb5_get_tickets) 756 k5destroy(); 757 758 /* Leave */ 759 exit(EXIT_SUCCESS); 760 } 761 #endif 762 763 static void 764 checknologin(char *fname) 765 { 766 int fd, nchars; 767 char tbuf[8192]; 768 769 if ((fd = open(fname ? fname : _PATH_NOLOGIN, O_RDONLY, 0)) >= 0) { 770 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0) 771 (void)write(fileno(stdout), tbuf, nchars); 772 sleepexit(EXIT_SUCCESS); 773 } 774 } 775 776 static void 777 usage(void) 778 { 779 (void)fprintf(stderr, 780 "Usage: %s [-Ffps] [-a address] [-h hostname] [username]\n", 781 getprogname()); 782 exit(EXIT_FAILURE); 783 } 784
Indexes created Tue Sep 30 20:09:53 GMT 2025