login.c revision 1.96
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 95 #ifdef KERBEROS5 96 int login_krb5_get_tickets = 1; 97 int login_krb5_forwardable_tgt = 0; 98 int login_krb5_retain_ccache = 0; 99 #endif 100 101 void badlogin(char *); 102 void checknologin(char *); 103 #ifdef SUPPORT_UTMP 104 static void doutmp(void); 105 static void dolastlog(int); 106 #endif 107 #ifdef SUPPORT_UTMPX 108 static void doutmpx(void); 109 static void dolastlogx(int); 110 #endif 111 static void update_db(int); 112 void getloginname(void); 113 void motd(char *); 114 int rootterm(char *); 115 void sigint(int); 116 void sleepexit(int); 117 const char *stypeof(const char *); 118 void timedout(int); 119 #ifdef KERBEROS5 120 int k5login(struct passwd *, char *, char *, char *); 121 void k5destroy(void); 122 int k5_read_creds(char*); 123 int k5_write_creds(void); 124 #endif 125 #if defined(KERBEROS5) 126 void dofork(void); 127 #endif 128 void decode_ss(const char *); 129 void usage(void); 130 131 #define TTYGRPNAME "tty" /* name of group to own ttys */ 132 133 #define DEFAULT_BACKOFF 3 134 #define DEFAULT_RETRIES 10 135 136 /* 137 * This bounds the time given to login. Not a define so it can 138 * be patched on machines where it's too small. 139 */ 140 u_int timeout = 300; 141 142 #if defined(KERBEROS5) 143 int notickets = 1; 144 char *instance; 145 int has_ccache = 0; 146 extern krb5_context kcontext; 147 extern int have_forward; 148 extern char *krb5tkfile_env; 149 extern int krb5_configured; 150 #endif 151 152 #if defined(KERBEROS5) 153 #define KERBEROS_CONFIGURED krb5_configured 154 #endif 155 156 struct passwd *pwd; 157 int failures, have_ss; 158 char term[64], *envinit[1], *hostname, *username, *tty, *nested; 159 struct timeval now; 160 struct sockaddr_storage ss; 161 162 extern const char copyrightstr[]; 163 164 int 165 main(int argc, char *argv[]) 166 { 167 extern char **environ; 168 struct group *gr; 169 struct stat st; 170 int ask, ch, cnt, fflag, hflag, pflag, sflag, quietlog, rootlogin, rval; 171 int Fflag; 172 uid_t uid, saved_uid; 173 gid_t saved_gid, saved_gids[NGROUPS_MAX]; 174 int nsaved_gids; 175 char *domain, *p, *ttyn, *pwprompt; 176 char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10]; 177 char localhost[MAXHOSTNAMELEN + 1]; 178 int need_chpass, require_chpass; 179 int login_retries = DEFAULT_RETRIES, 180 login_backoff = DEFAULT_BACKOFF; 181 time_t pw_warntime = _PASSWORD_WARNDAYS * SECSPERDAY; 182 #ifdef KERBEROS5 183 krb5_error_code kerror; 184 #endif 185 #if defined(KERBEROS5) 186 int got_tickets = 0; 187 #endif 188 #ifdef LOGIN_CAP 189 char *shell = NULL; 190 login_cap_t *lc = NULL; 191 #endif 192 193 tbuf[0] = '\0'; 194 rval = 0; 195 pwprompt = NULL; 196 nested = NULL; 197 need_chpass = require_chpass = 0; 198 199 (void)signal(SIGALRM, timedout); 200 (void)alarm(timeout); 201 (void)signal(SIGQUIT, SIG_IGN); 202 (void)signal(SIGINT, SIG_IGN); 203 (void)setpriority(PRIO_PROCESS, 0, 0); 204 205 openlog("login", 0, LOG_AUTH); 206 207 /* 208 * -p is used by getty to tell login not to destroy the environment 209 * -f is used to skip a second login authentication 210 * -h is used by other servers to pass the name of the remote host to 211 * login so that it may be placed in utmp/utmpx and wtmp/wtmpx 212 * -a in addition to -h, a server may supply -a to pass the actual 213 * server address. 214 * -s is used to force use of S/Key or equivalent. 215 */ 216 domain = NULL; 217 if (gethostname(localhost, sizeof(localhost)) < 0) 218 syslog(LOG_ERR, "couldn't get local hostname: %m"); 219 else 220 domain = strchr(localhost, '.'); 221 localhost[sizeof(localhost) - 1] = '\0'; 222 223 Fflag = fflag = hflag = pflag = sflag = 0; 224 have_ss = 0; 225 #ifdef KERBEROS5 226 have_forward = 0; 227 #endif 228 uid = getuid(); 229 while ((ch = getopt(argc, argv, "a:Ffh:ps")) != -1) 230 switch (ch) { 231 case 'a': 232 if (uid) 233 errx(EXIT_FAILURE, "-a option: %s", strerror(EPERM)); 234 decode_ss(optarg); 235 #ifdef notdef 236 (void)sockaddr_snprintf(optarg, 237 sizeof(struct sockaddr_storage), "%a", (void *)&ss); 238 #endif 239 break; 240 case 'F': 241 Fflag = 1; 242 /* FALLTHROUGH */ 243 case 'f': 244 fflag = 1; 245 break; 246 case 'h': 247 if (uid) 248 errx(EXIT_FAILURE, "-h option: %s", strerror(EPERM)); 249 hflag = 1; 250 #ifdef notdef 251 if (domain && (p = strchr(optarg, '.')) != NULL && 252 strcasecmp(p, domain) == 0) 253 *p = '\0'; 254 #endif 255 hostname = optarg; 256 break; 257 case 'p': 258 pflag = 1; 259 break; 260 case 's': 261 sflag = 1; 262 break; 263 default: 264 case '?': 265 usage(); 266 break; 267 } 268 269 setproctitle(NULL); 270 argc -= optind; 271 argv += optind; 272 273 if (*argv) { 274 username = *argv; 275 ask = 0; 276 } else 277 ask = 1; 278 279 #ifdef F_CLOSEM 280 (void)fcntl(3, F_CLOSEM, 0); 281 #else 282 for (cnt = getdtablesize(); cnt > 2; cnt--) 283 (void)close(cnt); 284 #endif 285 286 ttyn = ttyname(STDIN_FILENO); 287 if (ttyn == NULL || *ttyn == '\0') { 288 (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY); 289 ttyn = tname; 290 } 291 if ((tty = strstr(ttyn, "/pts/")) != NULL) 292 ++tty; 293 else if ((tty = strrchr(ttyn, '/')) != NULL) 294 ++tty; 295 else 296 tty = ttyn; 297 298 if (issetugid()) { 299 nested = strdup(user_from_uid(getuid(), 0)); 300 if (nested == NULL) { 301 syslog(LOG_ERR, "strdup: %m"); 302 sleepexit(EXIT_FAILURE); 303 } 304 } 305 306 #ifdef LOGIN_CAP 307 /* Get "login-retries" and "login-backoff" from default class */ 308 if ((lc = login_getclass(NULL)) != NULL) { 309 login_retries = (int)login_getcapnum(lc, "login-retries", 310 DEFAULT_RETRIES, DEFAULT_RETRIES); 311 login_backoff = (int)login_getcapnum(lc, "login-backoff", 312 DEFAULT_BACKOFF, DEFAULT_BACKOFF); 313 login_close(lc); 314 lc = NULL; 315 } 316 #endif 317 318 #ifdef KERBEROS5 319 kerror = krb5_init_context(&kcontext); 320 if (kerror) { 321 /* 322 * If Kerberos is not configured, that is, we are 323 * not using Kerberos, do not log the error message. 324 * However, if Kerberos is configured, and the 325 * context init fails for some other reason, we need 326 * to issue a no tickets warning to the user when the 327 * login succeeds. 328 */ 329 if (kerror != ENXIO) { /* XXX NetBSD-local Heimdal hack */ 330 syslog(LOG_NOTICE, 331 "%s when initializing Kerberos context", 332 error_message(kerror)); 333 krb5_configured = 1; 334 } 335 login_krb5_get_tickets = 0; 336 } 337 #endif /* KERBEROS5 */ 338 339 for (cnt = 0;; ask = 1) { 340 #if defined(KERBEROS5) 341 if (login_krb5_get_tickets) 342 k5destroy(); 343 #endif 344 if (ask) { 345 fflag = 0; 346 getloginname(); 347 } 348 rootlogin = 0; 349 #ifdef KERBEROS5 350 if ((instance = strchr(username, '/')) != NULL) 351 *instance++ = '\0'; 352 else 353 instance = ""; 354 #endif 355 if (strlen(username) > MAXLOGNAME) 356 username[MAXLOGNAME] = '\0'; 357 358 /* 359 * Note if trying multiple user names; log failures for 360 * previous user name, but don't bother logging one failure 361 * for nonexistent name (mistyped username). 362 */ 363 if (failures && strcmp(tbuf, username)) { 364 if (failures > (pwd ? 0 : 1)) 365 badlogin(tbuf); 366 failures = 0; 367 } 368 (void)strlcpy(tbuf, username, sizeof(tbuf)); 369 370 pwd = getpwnam(username); 371 372 #ifdef LOGIN_CAP 373 /* 374 * Establish the class now, before we might goto 375 * within the next block. pwd can be NULL since it 376 * falls back to the "default" class if it is. 377 */ 378 lc = login_getclass(pwd ? pwd->pw_class : NULL); 379 #endif 380 /* 381 * if we have a valid account name, and it doesn't have a 382 * password, or the -f option was specified and the caller 383 * is root or the caller isn't changing their uid, don't 384 * authenticate. 385 */ 386 if (pwd) { 387 if (pwd->pw_uid == 0) 388 rootlogin = 1; 389 390 if (fflag && (uid == 0 || uid == pwd->pw_uid)) { 391 /* already authenticated */ 392 #ifdef KERBEROS5 393 if (login_krb5_get_tickets && Fflag) 394 k5_read_creds(username); 395 #endif 396 break; 397 } else if (pwd->pw_passwd[0] == '\0') { 398 /* pretend password okay */ 399 rval = 0; 400 goto ttycheck; 401 } 402 } 403 404 fflag = 0; 405 406 (void)setpriority(PRIO_PROCESS, 0, -4); 407 408 #ifdef SKEY 409 if (skey_haskey(username) == 0) { 410 static char skprompt[80]; 411 const char *skinfo = skey_keyinfo(username); 412 413 (void)snprintf(skprompt, sizeof(skprompt), 414 "Password [ %s ]:", 415 skinfo ? skinfo : "error getting challenge"); 416 pwprompt = skprompt; 417 } else 418 #endif 419 pwprompt = "Password:"; 420 421 p = getpass(pwprompt); 422 423 if (pwd == NULL) { 424 rval = 1; 425 goto skip; 426 } 427 #ifdef KERBEROS5 428 if (login_krb5_get_tickets && 429 k5login(pwd, instance, localhost, p) == 0) { 430 rval = 0; 431 got_tickets = 1; 432 } 433 #endif 434 #if defined(KERBEROS5) 435 if (got_tickets) 436 goto skip; 437 #endif 438 #ifdef SKEY 439 if (skey_haskey(username) == 0 && 440 skey_passcheck(username, p) != -1) { 441 rval = 0; 442 goto skip; 443 } 444 #endif 445 if (!sflag && *pwd->pw_passwd != '\0' && 446 !strcmp(crypt(p, pwd->pw_passwd), pwd->pw_passwd)) { 447 rval = 0; 448 require_chpass = 1; 449 goto skip; 450 } 451 rval = 1; 452 453 skip: 454 memset(p, 0, strlen(p)); 455 456 (void)setpriority(PRIO_PROCESS, 0, 0); 457 458 ttycheck: 459 /* 460 * If trying to log in as root without Kerberos, 461 * but with insecure terminal, refuse the login attempt. 462 */ 463 if (pwd && !rval && rootlogin && !rootterm(tty)) { 464 (void)printf("Login incorrect or refused on this " 465 "terminal.\n"); 466 if (hostname) 467 syslog(LOG_NOTICE, 468 "LOGIN %s REFUSED FROM %s ON TTY %s", 469 pwd->pw_name, hostname, tty); 470 else 471 syslog(LOG_NOTICE, 472 "LOGIN %s REFUSED ON TTY %s", 473 pwd->pw_name, tty); 474 continue; 475 } 476 477 if (pwd && !rval) 478 break; 479 480 (void)printf("Login incorrect or refused on this " 481 "terminal.\n"); 482 failures++; 483 cnt++; 484 /* 485 * We allow login_retries tries, but after login_backoff 486 * we start backing off. These default to 10 and 3 487 * respectively. 488 */ 489 if (cnt > login_backoff) { 490 if (cnt >= login_retries) { 491 badlogin(username); 492 sleepexit(EXIT_FAILURE); 493 } 494 sleep((u_int)((cnt - login_backoff) * 5)); 495 } 496 } 497 498 /* committed to login -- turn off timeout */ 499 (void)alarm((u_int)0); 500 501 endpwent(); 502 503 /* if user not super-user, check for disabled logins */ 504 #ifdef LOGIN_CAP 505 if (!login_getcapbool(lc, "ignorenologin", rootlogin)) 506 checknologin(login_getcapstr(lc, "nologin", NULL, NULL)); 507 #else 508 if (!rootlogin) 509 checknologin(NULL); 510 #endif 511 512 #ifdef LOGIN_CAP 513 quietlog = login_getcapbool(lc, "hushlogin", 0); 514 #else 515 quietlog = 0; 516 #endif 517 /* Temporarily give up special privileges so we can change */ 518 /* into NFS-mounted homes that are exported for non-root */ 519 /* access and have mode 7x0 */ 520 saved_uid = geteuid(); 521 saved_gid = getegid(); 522 nsaved_gids = getgroups(NGROUPS_MAX, saved_gids); 523 524 (void)setegid(pwd->pw_gid); 525 initgroups(username, pwd->pw_gid); 526 (void)seteuid(pwd->pw_uid); 527 528 if (chdir(pwd->pw_dir) < 0) { 529 #ifdef LOGIN_CAP 530 if (login_getcapbool(lc, "requirehome", 0)) { 531 (void)printf("Home directory %s required\n", 532 pwd->pw_dir); 533 sleepexit(EXIT_FAILURE); 534 } 535 #endif 536 (void)printf("No home directory %s!\n", pwd->pw_dir); 537 if (chdir("/") == -1) 538 exit(EXIT_FAILURE); 539 pwd->pw_dir = "/"; 540 (void)printf("Logging in with home = \"/\".\n"); 541 } 542 543 if (!quietlog) 544 quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0; 545 546 /* regain special privileges */ 547 (void)seteuid(saved_uid); 548 setgroups(nsaved_gids, saved_gids); 549 (void)setegid(saved_gid); 550 551 #ifdef LOGIN_CAP 552 pw_warntime = login_getcaptime(lc, "password-warn", 553 _PASSWORD_WARNDAYS * SECSPERDAY, 554 _PASSWORD_WARNDAYS * SECSPERDAY); 555 #endif 556 557 (void)gettimeofday(&now, (struct timezone *)NULL); 558 if (pwd->pw_expire) { 559 if (now.tv_sec >= pwd->pw_expire) { 560 (void)printf("Sorry -- your account has expired.\n"); 561 sleepexit(EXIT_FAILURE); 562 } else if (pwd->pw_expire - now.tv_sec < pw_warntime && 563 !quietlog) 564 (void)printf("Warning: your account expires on %s", 565 ctime(&pwd->pw_expire)); 566 } 567 if (pwd->pw_change) { 568 if (pwd->pw_change == _PASSWORD_CHGNOW) 569 need_chpass = 1; 570 else if (now.tv_sec >= pwd->pw_change) { 571 (void)printf("Sorry -- your password has expired.\n"); 572 sleepexit(EXIT_FAILURE); 573 } else if (pwd->pw_change - now.tv_sec < pw_warntime && 574 !quietlog) 575 (void)printf("Warning: your password expires on %s", 576 ctime(&pwd->pw_change)); 577 578 } 579 /* Nothing else left to fail -- really log in. */ 580 update_db(quietlog); 581 582 (void)chown(ttyn, pwd->pw_uid, 583 (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid); 584 585 if (ttyaction(ttyn, "login", pwd->pw_name)) 586 (void)printf("Warning: ttyaction failed.\n"); 587 588 #if defined(KERBEROS5) 589 /* Fork so that we can call kdestroy */ 590 if (! login_krb5_retain_ccache && has_ccache) 591 dofork(); 592 #endif 593 594 /* Destroy environment unless user has requested its preservation. */ 595 if (!pflag) 596 environ = envinit; 597 598 #ifdef LOGIN_CAP 599 if (nested == NULL && setusercontext(lc, pwd, pwd->pw_uid, 600 LOGIN_SETLOGIN) != 0) { 601 syslog(LOG_ERR, "setusercontext failed"); 602 exit(EXIT_FAILURE); 603 } 604 if (setusercontext(lc, pwd, pwd->pw_uid, 605 (LOGIN_SETALL & ~(LOGIN_SETPATH|LOGIN_SETLOGIN))) != 0) { 606 syslog(LOG_ERR, "setusercontext failed"); 607 exit(EXIT_FAILURE); 608 } 609 #else 610 (void)setgid(pwd->pw_gid); 611 612 initgroups(username, pwd->pw_gid); 613 614 if (nested == NULL && setlogin(pwd->pw_name) < 0) 615 syslog(LOG_ERR, "setlogin() failure: %m"); 616 617 /* Discard permissions last so can't get killed and drop core. */ 618 if (rootlogin) 619 (void)setuid(0); 620 else 621 (void)setuid(pwd->pw_uid); 622 #endif 623 624 if (*pwd->pw_shell == '\0') 625 pwd->pw_shell = _PATH_BSHELL; 626 #ifdef LOGIN_CAP 627 if ((shell = login_getcapstr(lc, "shell", NULL, NULL)) != NULL) { 628 if ((shell = strdup(shell)) == NULL) { 629 syslog(LOG_ERR, "Cannot alloc mem"); 630 sleepexit(EXIT_FAILURE); 631 } 632 pwd->pw_shell = shell; 633 } 634 #endif 635 636 (void)setenv("HOME", pwd->pw_dir, 1); 637 (void)setenv("SHELL", pwd->pw_shell, 1); 638 if (term[0] == '\0') { 639 char *tt = (char *)stypeof(tty); 640 #ifdef LOGIN_CAP 641 if (tt == NULL) 642 tt = login_getcapstr(lc, "term", NULL, NULL); 643 #endif 644 /* unknown term -> "su" */ 645 (void)strlcpy(term, tt != NULL ? tt : "su", sizeof(term)); 646 } 647 (void)setenv("TERM", term, 0); 648 (void)setenv("LOGNAME", pwd->pw_name, 1); 649 (void)setenv("USER", pwd->pw_name, 1); 650 651 #ifdef LOGIN_CAP 652 setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETPATH); 653 #else 654 (void)setenv("PATH", _PATH_DEFPATH, 0); 655 #endif 656 657 #ifdef KERBEROS5 658 if (krb5tkfile_env) 659 (void)setenv("KRB5CCNAME", krb5tkfile_env, 1); 660 #endif 661 662 if (tty[sizeof("tty")-1] == 'd') 663 syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name); 664 665 /* If fflag is on, assume caller/authenticator has logged root login. */ 666 if (rootlogin && fflag == 0) { 667 if (hostname) 668 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s", 669 username, tty, hostname); 670 else 671 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s", 672 username, tty); 673 } 674 675 #if defined(KERBEROS5) 676 if (KERBEROS_CONFIGURED && !quietlog && notickets == 1) 677 (void)printf("Warning: no Kerberos tickets issued.\n"); 678 #endif 679 680 if (!quietlog) { 681 char *fname; 682 #ifdef LOGIN_CAP 683 fname = login_getcapstr(lc, "copyright", NULL, NULL); 684 if (fname != NULL && access(fname, F_OK) == 0) 685 motd(fname); 686 else 687 #endif 688 (void)printf("%s", copyrightstr); 689 690 #ifdef LOGIN_CAP 691 fname = login_getcapstr(lc, "welcome", NULL, NULL); 692 if (fname == NULL || access(fname, F_OK) != 0) 693 #endif 694 fname = _PATH_MOTDFILE; 695 motd(fname); 696 697 (void)snprintf(tbuf, 698 sizeof(tbuf), "%s/%s", _PATH_MAILDIR, pwd->pw_name); 699 if (stat(tbuf, &st) == 0 && st.st_size != 0) 700 (void)printf("You have %smail.\n", 701 (st.st_mtime > st.st_atime) ? "new " : ""); 702 } 703 704 #ifdef LOGIN_CAP 705 login_close(lc); 706 #endif 707 708 (void)signal(SIGALRM, SIG_DFL); 709 (void)signal(SIGQUIT, SIG_DFL); 710 (void)signal(SIGINT, SIG_DFL); 711 (void)signal(SIGTSTP, SIG_IGN); 712 713 tbuf[0] = '-'; 714 (void)strlcpy(tbuf + 1, (p = strrchr(pwd->pw_shell, '/')) ? 715 p + 1 : pwd->pw_shell, sizeof(tbuf) - 1); 716 717 /* Wait to change password until we're unprivileged */ 718 if (need_chpass) { 719 if (!require_chpass) 720 (void)printf( 721 "Warning: your password has expired. Please change it as soon as possible.\n"); 722 else { 723 int status; 724 725 (void)printf( 726 "Your password has expired. Please choose a new one.\n"); 727 switch (fork()) { 728 case -1: 729 warn("fork"); 730 sleepexit(EXIT_FAILURE); 731 case 0: 732 execl(_PATH_BINPASSWD, "passwd", NULL); 733 _exit(EXIT_FAILURE); 734 default: 735 if (wait(&status) == -1 || 736 WEXITSTATUS(status)) 737 sleepexit(EXIT_FAILURE); 738 } 739 } 740 } 741 742 #ifdef KERBEROS5 743 if (login_krb5_get_tickets) 744 k5_write_creds(); 745 #endif 746 execlp(pwd->pw_shell, tbuf, NULL); 747 err(EXIT_FAILURE, "%s", pwd->pw_shell); 748 } 749 750 #if defined(KERBEROS5) 751 #define NBUFSIZ (MAXLOGNAME + 1 + 5) /* .root suffix */ 752 #else 753 #define NBUFSIZ (MAXLOGNAME + 1) 754 #endif 755 756 #if defined(KERBEROS5) 757 /* 758 * This routine handles cleanup stuff, and the like. 759 * It exists only in the child process. 760 */ 761 void 762 dofork(void) 763 { 764 pid_t child, wchild; 765 766 switch (child = fork()) { 767 case 0: 768 return; /* Child process */ 769 case -1: 770 err(EXIT_FAILURE, "Can't fork"); 771 /*NOTREACHED*/ 772 default: 773 break; 774 } 775 776 /* 777 * Setup stuff? This would be things we could do in parallel 778 * with login 779 */ 780 if (chdir("/") == -1) /* Let's not keep the fs busy... */ 781 err(EXIT_FAILURE, "Can't chdir to `/'"); 782 783 /* If we're the parent, watch the child until it dies */ 784 while ((wchild = wait(NULL)) != child) 785 if (wchild == -1) 786 err(EXIT_FAILURE, "Can't wait"); 787 788 /* Cleanup stuff */ 789 /* Run kdestroy to destroy tickets */ 790 if (login_krb5_get_tickets) 791 k5destroy(); 792 793 /* Leave */ 794 exit(EXIT_SUCCESS); 795 } 796 #endif 797 798 void 799 getloginname(void) 800 { 801 int ch; 802 char *p; 803 static char nbuf[NBUFSIZ]; 804 805 for (;;) { 806 (void)printf("login: "); 807 for (p = nbuf; (ch = getchar()) != '\n'; ) { 808 if (ch == EOF) { 809 badlogin(username); 810 exit(EXIT_FAILURE); 811 } 812 if (p < nbuf + (NBUFSIZ - 1)) 813 *p++ = ch; 814 } 815 if (p > nbuf) { 816 if (nbuf[0] == '-') 817 (void)fprintf(stderr, 818 "login names may not start with '-'.\n"); 819 else { 820 *p = '\0'; 821 username = nbuf; 822 break; 823 } 824 } 825 } 826 } 827 828 int 829 rootterm(char *ttyn) 830 { 831 struct ttyent *t; 832 833 return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE); 834 } 835 836 jmp_buf motdinterrupt; 837 838 void 839 motd(char *fname) 840 { 841 int fd, nchars; 842 sig_t oldint; 843 char tbuf[8192]; 844 845 if ((fd = open(fname ? fname : _PATH_MOTDFILE, O_RDONLY, 0)) < 0) 846 return; 847 oldint = signal(SIGINT, sigint); 848 if (setjmp(motdinterrupt) == 0) 849 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0) 850 (void)write(fileno(stdout), tbuf, nchars); 851 (void)signal(SIGINT, oldint); 852 (void)close(fd); 853 } 854 855 /* ARGSUSED */ 856 void 857 sigint(int signo) 858 { 859 860 longjmp(motdinterrupt, 1); 861 } 862 863 /* ARGSUSED */ 864 void 865 timedout(int signo) 866 { 867 868 (void)fprintf(stderr, "Login timed out after %d seconds\n", timeout); 869 exit(EXIT_FAILURE); 870 } 871 872 void 873 checknologin(char *fname) 874 { 875 int fd, nchars; 876 char tbuf[8192]; 877 878 if ((fd = open(fname ? fname : _PATH_NOLOGIN, O_RDONLY, 0)) >= 0) { 879 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0) 880 (void)write(fileno(stdout), tbuf, nchars); 881 sleepexit(EXIT_SUCCESS); 882 } 883 } 884 885 static void 886 update_db(int quietlog) 887 { 888 if (nested != NULL) { 889 if (hostname != NULL) 890 syslog(LOG_NOTICE, "%s to %s on tty %s from %s", 891 nested, pwd->pw_name, tty, hostname); 892 else 893 syslog(LOG_NOTICE, "%s to %s on tty %s", nested, 894 pwd->pw_name, tty); 895 896 return; 897 } 898 if (hostname != NULL && have_ss == 0) { 899 socklen_t len = sizeof(ss); 900 have_ss = getpeername(STDIN_FILENO, (struct sockaddr *)&ss, 901 &len) != -1; 902 } 903 (void)gettimeofday(&now, NULL); 904 #ifdef SUPPORT_UTMPX 905 doutmpx(); 906 dolastlogx(quietlog); 907 quietlog = 1; 908 #endif 909 #ifdef SUPPORT_UTMP 910 doutmp(); 911 dolastlog(quietlog); 912 #endif 913 } 914 915 #ifdef SUPPORT_UTMPX 916 static void 917 doutmpx(void) 918 { 919 struct utmpx utmpx; 920 char *t; 921 922 memset((void *)&utmpx, 0, sizeof(utmpx)); 923 utmpx.ut_tv = now; 924 (void)strncpy(utmpx.ut_name, username, sizeof(utmpx.ut_name)); 925 if (hostname) { 926 (void)strncpy(utmpx.ut_host, hostname, sizeof(utmpx.ut_host)); 927 utmpx.ut_ss = ss; 928 } 929 (void)strncpy(utmpx.ut_line, tty, sizeof(utmpx.ut_line)); 930 utmpx.ut_type = USER_PROCESS; 931 utmpx.ut_pid = getpid(); 932 t = tty + strlen(tty); 933 if (t - tty >= sizeof(utmpx.ut_id)) { 934 (void)strncpy(utmpx.ut_id, t - sizeof(utmpx.ut_id), 935 sizeof(utmpx.ut_id)); 936 } else { 937 (void)strncpy(utmpx.ut_id, tty, sizeof(utmpx.ut_id)); 938 } 939 if (pututxline(&utmpx) == NULL) 940 syslog(LOG_NOTICE, "Cannot update utmpx: %m"); 941 endutxent(); 942 if (updwtmpx(_PATH_WTMPX, &utmpx) != 0) 943 syslog(LOG_NOTICE, "Cannot update wtmpx: %m"); 944 } 945 946 static void 947 dolastlogx(int quiet) 948 { 949 struct lastlogx ll; 950 if (!quiet && getlastlogx(_PATH_LASTLOGX, pwd->pw_uid, &ll) != NULL) { 951 time_t t = (time_t)ll.ll_tv.tv_sec; 952 (void)printf("Last login: %.24s ", ctime(&t)); 953 if (*ll.ll_host != '\0') 954 (void)printf("from %.*s ", 955 (int)sizeof(ll.ll_host), 956 ll.ll_host); 957 (void)printf("on %.*s\n", 958 (int)sizeof(ll.ll_line), 959 ll.ll_line); 960 } 961 ll.ll_tv = now; 962 (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line)); 963 if (hostname) 964 (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host)); 965 else 966 (void)memset(ll.ll_host, '\0', sizeof(ll.ll_host)); 967 if (have_ss) 968 ll.ll_ss = ss; 969 else 970 (void)memset(&ll.ll_ss, 0, sizeof(ll.ll_ss)); 971 if (updlastlogx(_PATH_LASTLOGX, pwd->pw_uid, &ll) != 0) 972 syslog(LOG_NOTICE, "Cannot update lastlogx: %m"); 973 } 974 #endif 975 976 #ifdef SUPPORT_UTMP 977 static void 978 doutmp(void) 979 { 980 struct utmp utmp; 981 982 (void)memset((void *)&utmp, 0, sizeof(utmp)); 983 utmp.ut_time = now.tv_sec; 984 (void)strncpy(utmp.ut_name, username, sizeof(utmp.ut_name)); 985 if (hostname) 986 (void)strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host)); 987 (void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line)); 988 login(&utmp); 989 } 990 991 static void 992 dolastlog(int quiet) 993 { 994 struct lastlog ll; 995 int fd; 996 997 if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) >= 0) { 998 (void)lseek(fd, (off_t)(pwd->pw_uid * sizeof(ll)), SEEK_SET); 999 if (!quiet) { 1000 if (read(fd, (char *)&ll, sizeof(ll)) == sizeof(ll) && 1001 ll.ll_time != 0) { 1002 (void)printf("Last login: %.24s ", 1003 ctime(&ll.ll_time)); 1004 if (*ll.ll_host != '\0') 1005 (void)printf("from %.*s ", 1006 (int)sizeof(ll.ll_host), 1007 ll.ll_host); 1008 (void)printf("on %.*s\n", 1009 (int)sizeof(ll.ll_line), ll.ll_line); 1010 } 1011 (void)lseek(fd, (off_t)(pwd->pw_uid * sizeof(ll)), 1012 SEEK_SET); 1013 } 1014 memset((void *)&ll, 0, sizeof(ll)); 1015 ll.ll_time = now.tv_sec; 1016 (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line)); 1017 if (hostname) 1018 (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host)); 1019 (void)write(fd, (char *)&ll, sizeof(ll)); 1020 (void)close(fd); 1021 } 1022 } 1023 #endif 1024 1025 void 1026 badlogin(char *name) 1027 { 1028 1029 if (failures == 0) 1030 return; 1031 if (hostname) { 1032 syslog(LOG_NOTICE, "%d LOGIN FAILURE%s FROM %s", 1033 failures, failures > 1 ? "S" : "", hostname); 1034 syslog(LOG_AUTHPRIV|LOG_NOTICE, 1035 "%d LOGIN FAILURE%s FROM %s, %s", 1036 failures, failures > 1 ? "S" : "", hostname, name); 1037 } else { 1038 syslog(LOG_NOTICE, "%d LOGIN FAILURE%s ON %s", 1039 failures, failures > 1 ? "S" : "", tty); 1040 syslog(LOG_AUTHPRIV|LOG_NOTICE, 1041 "%d LOGIN FAILURE%s ON %s, %s", 1042 failures, failures > 1 ? "S" : "", tty, name); 1043 } 1044 } 1045 1046 const char * 1047 stypeof(const char *ttyid) 1048 { 1049 struct ttyent *t; 1050 1051 return (ttyid && (t = getttynam(ttyid)) ? t->ty_type : NULL); 1052 } 1053 1054 void 1055 sleepexit(int eval) 1056 { 1057 1058 (void)sleep(5); 1059 exit(eval); 1060 } 1061 1062 void 1063 decode_ss(const char *arg) 1064 { 1065 struct sockaddr_storage *ssp; 1066 size_t len = strlen(arg); 1067 1068 if (len > sizeof(*ssp) * 4 + 1 || len < sizeof(*ssp)) 1069 errx(EXIT_FAILURE, "Bad argument"); 1070 1071 if ((ssp = malloc(len)) == NULL) 1072 err(EXIT_FAILURE, NULL); 1073 1074 if (strunvis((char *)ssp, arg) != sizeof(*ssp)) 1075 errx(EXIT_FAILURE, "Decoding error"); 1076 1077 (void)memcpy(&ss, ssp, sizeof(ss)); 1078 have_ss = 1; 1079 } 1080 1081 void 1082 usage(void) 1083 { 1084 (void)fprintf(stderr, 1085 "Usage: %s [-Ffps] [-a address] [-h hostname] [username]\n", 1086 getprogname()); 1087 exit(EXIT_FAILURE); 1088 } 1089
Indexes created Wed Oct 01 13:09:50 GMT 2025