login.c revision 1.95
1 /* $NetBSD: login.c,v 1.95 2007/05/09 01:56:25 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( 35 "@(#) Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994\n\ 36 The Regents of the University of California. All rights reserved.\n"); 37 #endif /* not lint */ 38 39 #ifndef lint 40 #if 0 41 static char sccsid[] = "@(#)login.c 8.4 (Berkeley) 4/2/94"; 42 #endif 43 __RCSID("$NetBSD: login.c,v 1.95 2007/05/09 01:56:25 christos Exp $"); 44 #endif /* not lint */ 45 46 /* 47 * login [ name ] 48 * login -h hostname (for telnetd, etc.) 49 * login -f name (for pre-authenticated login: datakit, xterm, etc.) 50 */ 51 52 #include <sys/param.h> 53 #include <sys/stat.h> 54 #include <sys/time.h> 55 #include <sys/resource.h> 56 #include <sys/file.h> 57 #include <sys/wait.h> 58 #include <sys/socket.h> 59 60 #include <err.h> 61 #include <errno.h> 62 #include <grp.h> 63 #include <pwd.h> 64 #include <setjmp.h> 65 #include <signal.h> 66 #include <stdio.h> 67 #include <stdlib.h> 68 #include <string.h> 69 #include <syslog.h> 70 #include <time.h> 71 #include <ttyent.h> 72 #include <tzfile.h> 73 #include <unistd.h> 74 #include <sysexits.h> 75 #ifdef SUPPORT_UTMP 76 #include <utmp.h> 77 #endif 78 #ifdef SUPPORT_UTMPX 79 #include <utmpx.h> 80 #endif 81 #include <util.h> 82 #ifdef SKEY 83 #include <skey.h> 84 #endif 85 #ifdef KERBEROS5 86 #include <krb5/krb5.h> 87 #include <com_err.h> 88 #endif 89 #ifdef LOGIN_CAP 90 #include <login_cap.h> 91 #endif 92 #include <vis.h> 93 94 #include "pathnames.h" 95 96 #ifdef KERBEROS5 97 int login_krb5_get_tickets = 1; 98 int login_krb5_forwardable_tgt = 0; 99 int login_krb5_retain_ccache = 0; 100 #endif 101 102 void badlogin(char *); 103 void checknologin(char *); 104 #ifdef SUPPORT_UTMP 105 static void doutmp(void); 106 static void dolastlog(int); 107 #endif 108 #ifdef SUPPORT_UTMPX 109 static void doutmpx(void); 110 static void dolastlogx(int); 111 #endif 112 static void update_db(int); 113 void getloginname(void); 114 void motd(char *); 115 int rootterm(char *); 116 void sigint(int); 117 void sleepexit(int); 118 const char *stypeof(const char *); 119 void timedout(int); 120 #ifdef KERBEROS5 121 int k5login(struct passwd *, char *, char *, char *); 122 void k5destroy(void); 123 int k5_read_creds(char*); 124 int k5_write_creds(void); 125 #endif 126 #if defined(KERBEROS5) 127 void dofork(void); 128 #endif 129 void decode_ss(const char *); 130 void usage(void); 131 132 #define TTYGRPNAME "tty" /* name of group to own ttys */ 133 134 #define DEFAULT_BACKOFF 3 135 #define DEFAULT_RETRIES 10 136 137 /* 138 * This bounds the time given to login. Not a define so it can 139 * be patched on machines where it's too small. 140 */ 141 u_int timeout = 300; 142 143 #if defined(KERBEROS5) 144 int notickets = 1; 145 char *instance; 146 int has_ccache = 0; 147 extern krb5_context kcontext; 148 extern int have_forward; 149 extern char *krb5tkfile_env; 150 extern int krb5_configured; 151 #endif 152 153 #if defined(KERBEROS5) 154 #define KERBEROS_CONFIGURED krb5_configured 155 #endif 156 157 struct passwd *pwd; 158 int failures, have_ss; 159 char term[64], *envinit[1], *hostname, *username, *tty, *nested; 160 struct timeval now; 161 struct sockaddr_storage ss; 162 163 extern const char copyrightstr[]; 164 165 int 166 main(int argc, char *argv[]) 167 { 168 extern char **environ; 169 struct group *gr; 170 struct stat st; 171 int ask, ch, cnt, fflag, hflag, pflag, sflag, quietlog, rootlogin, rval; 172 int Fflag; 173 uid_t uid, saved_uid; 174 gid_t saved_gid, saved_gids[NGROUPS_MAX]; 175 int nsaved_gids; 176 char *domain, *p, *ttyn, *pwprompt; 177 char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10]; 178 char localhost[MAXHOSTNAMELEN + 1]; 179 int need_chpass, require_chpass; 180 int login_retries = DEFAULT_RETRIES, 181 login_backoff = DEFAULT_BACKOFF; 182 time_t pw_warntime = _PASSWORD_WARNDAYS * SECSPERDAY; 183 #ifdef KERBEROS5 184 krb5_error_code kerror; 185 #endif 186 #if defined(KERBEROS5) 187 int got_tickets = 0; 188 #endif 189 #ifdef LOGIN_CAP 190 char *shell = NULL; 191 login_cap_t *lc = NULL; 192 #endif 193 194 tbuf[0] = '\0'; 195 rval = 0; 196 pwprompt = NULL; 197 nested = NULL; 198 need_chpass = require_chpass = 0; 199 200 (void)signal(SIGALRM, timedout); 201 (void)alarm(timeout); 202 (void)signal(SIGQUIT, SIG_IGN); 203 (void)signal(SIGINT, SIG_IGN); 204 (void)setpriority(PRIO_PROCESS, 0, 0); 205 206 openlog("login", 0, LOG_AUTH); 207 208 /* 209 * -p is used by getty to tell login not to destroy the environment 210 * -f is used to skip a second login authentication 211 * -h is used by other servers to pass the name of the remote host to 212 * login so that it may be placed in utmp/utmpx and wtmp/wtmpx 213 * -a in addition to -h, a server may supply -a to pass the actual 214 * server address. 215 * -s is used to force use of S/Key or equivalent. 216 */ 217 domain = NULL; 218 if (gethostname(localhost, sizeof(localhost)) < 0) 219 syslog(LOG_ERR, "couldn't get local hostname: %m"); 220 else 221 domain = strchr(localhost, '.'); 222 localhost[sizeof(localhost) - 1] = '\0'; 223 224 Fflag = fflag = hflag = pflag = sflag = 0; 225 have_ss = 0; 226 #ifdef KERBEROS5 227 have_forward = 0; 228 #endif 229 uid = getuid(); 230 while ((ch = getopt(argc, argv, "a:Ffh:ps")) != -1) 231 switch (ch) { 232 case 'a': 233 if (uid) 234 errx(EXIT_FAILURE, "-a option: %s", strerror(EPERM)); 235 decode_ss(optarg); 236 #ifdef notdef 237 (void)sockaddr_snprintf(optarg, 238 sizeof(struct sockaddr_storage), "%a", (void *)&ss); 239 #endif 240 break; 241 case 'F': 242 Fflag = 1; 243 /* FALLTHROUGH */ 244 case 'f': 245 fflag = 1; 246 break; 247 case 'h': 248 if (uid) 249 errx(EXIT_FAILURE, "-h option: %s", strerror(EPERM)); 250 hflag = 1; 251 #ifdef notdef 252 if (domain && (p = strchr(optarg, '.')) != NULL && 253 strcasecmp(p, domain) == 0) 254 *p = '\0'; 255 #endif 256 hostname = optarg; 257 break; 258 case 'p': 259 pflag = 1; 260 break; 261 case 's': 262 sflag = 1; 263 break; 264 default: 265 case '?': 266 usage(); 267 break; 268 } 269 270 setproctitle(NULL); 271 argc -= optind; 272 argv += optind; 273 274 if (*argv) { 275 username = *argv; 276 ask = 0; 277 } else 278 ask = 1; 279 280 #ifdef F_CLOSEM 281 (void)fcntl(3, F_CLOSEM, 0); 282 #else 283 for (cnt = getdtablesize(); cnt > 2; cnt--) 284 (void)close(cnt); 285 #endif 286 287 ttyn = ttyname(STDIN_FILENO); 288 if (ttyn == NULL || *ttyn == '\0') { 289 (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY); 290 ttyn = tname; 291 } 292 if ((tty = strstr(ttyn, "/pts/")) != NULL) 293 ++tty; 294 else if ((tty = strrchr(ttyn, '/')) != NULL) 295 ++tty; 296 else 297 tty = ttyn; 298 299 if (issetugid()) { 300 nested = strdup(user_from_uid(getuid(), 0)); 301 if (nested == NULL) { 302 syslog(LOG_ERR, "strdup: %m"); 303 sleepexit(EXIT_FAILURE); 304 } 305 } 306 307 #ifdef LOGIN_CAP 308 /* Get "login-retries" and "login-backoff" from default class */ 309 if ((lc = login_getclass(NULL)) != NULL) { 310 login_retries = (int)login_getcapnum(lc, "login-retries", 311 DEFAULT_RETRIES, DEFAULT_RETRIES); 312 login_backoff = (int)login_getcapnum(lc, "login-backoff", 313 DEFAULT_BACKOFF, DEFAULT_BACKOFF); 314 login_close(lc); 315 lc = NULL; 316 } 317 #endif 318 319 #ifdef KERBEROS5 320 kerror = krb5_init_context(&kcontext); 321 if (kerror) { 322 /* 323 * If Kerberos is not configured, that is, we are 324 * not using Kerberos, do not log the error message. 325 * However, if Kerberos is configured, and the 326 * context init fails for some other reason, we need 327 * to issue a no tickets warning to the user when the 328 * login succeeds. 329 */ 330 if (kerror != ENXIO) { /* XXX NetBSD-local Heimdal hack */ 331 syslog(LOG_NOTICE, 332 "%s when initializing Kerberos context", 333 error_message(kerror)); 334 krb5_configured = 1; 335 } 336 login_krb5_get_tickets = 0; 337 } 338 #endif /* KERBEROS5 */ 339 340 for (cnt = 0;; ask = 1) { 341 #if defined(KERBEROS5) 342 if (login_krb5_get_tickets) 343 k5destroy(); 344 #endif 345 if (ask) { 346 fflag = 0; 347 getloginname(); 348 } 349 rootlogin = 0; 350 #ifdef KERBEROS5 351 if ((instance = strchr(username, '/')) != NULL) 352 *instance++ = '\0'; 353 else 354 instance = ""; 355 #endif 356 if (strlen(username) > MAXLOGNAME) 357 username[MAXLOGNAME] = '\0'; 358 359 /* 360 * Note if trying multiple user names; log failures for 361 * previous user name, but don't bother logging one failure 362 * for nonexistent name (mistyped username). 363 */ 364 if (failures && strcmp(tbuf, username)) { 365 if (failures > (pwd ? 0 : 1)) 366 badlogin(tbuf); 367 failures = 0; 368 } 369 (void)strlcpy(tbuf, username, sizeof(tbuf)); 370 371 pwd = getpwnam(username); 372 373 #ifdef LOGIN_CAP 374 /* 375 * Establish the class now, before we might goto 376 * within the next block. pwd can be NULL since it 377 * falls back to the "default" class if it is. 378 */ 379 lc = login_getclass(pwd ? pwd->pw_class : NULL); 380 #endif 381 /* 382 * if we have a valid account name, and it doesn't have a 383 * password, or the -f option was specified and the caller 384 * is root or the caller isn't changing their uid, don't 385 * authenticate. 386 */ 387 if (pwd) { 388 if (pwd->pw_uid == 0) 389 rootlogin = 1; 390 391 if (fflag && (uid == 0 || uid == pwd->pw_uid)) { 392 /* already authenticated */ 393 #ifdef KERBEROS5 394 if (login_krb5_get_tickets && Fflag) 395 k5_read_creds(username); 396 #endif 397 break; 398 } else if (pwd->pw_passwd[0] == '\0') { 399 /* pretend password okay */ 400 rval = 0; 401 goto ttycheck; 402 } 403 } 404 405 fflag = 0; 406 407 (void)setpriority(PRIO_PROCESS, 0, -4); 408 409 #ifdef SKEY 410 if (skey_haskey(username) == 0) { 411 static char skprompt[80]; 412 const char *skinfo = skey_keyinfo(username); 413 414 (void)snprintf(skprompt, sizeof(skprompt), 415 "Password [ %s ]:", 416 skinfo ? skinfo : "error getting challenge"); 417 pwprompt = skprompt; 418 } else 419 #endif 420 pwprompt = "Password:"; 421 422 p = getpass(pwprompt); 423 424 if (pwd == NULL) { 425 rval = 1; 426 goto skip; 427 } 428 #ifdef KERBEROS5 429 if (login_krb5_get_tickets && 430 k5login(pwd, instance, localhost, p) == 0) { 431 rval = 0; 432 got_tickets = 1; 433 } 434 #endif 435 #if defined(KERBEROS5) 436 if (got_tickets) 437 goto skip; 438 #endif 439 #ifdef SKEY 440 if (skey_haskey(username) == 0 && 441 skey_passcheck(username, p) != -1) { 442 rval = 0; 443 goto skip; 444 } 445 #endif 446 if (!sflag && *pwd->pw_passwd != '\0' && 447 !strcmp(crypt(p, pwd->pw_passwd), pwd->pw_passwd)) { 448 rval = 0; 449 require_chpass = 1; 450 goto skip; 451 } 452 rval = 1; 453 454 skip: 455 memset(p, 0, strlen(p)); 456 457 (void)setpriority(PRIO_PROCESS, 0, 0); 458 459 ttycheck: 460 /* 461 * If trying to log in as root without Kerberos, 462 * but with insecure terminal, refuse the login attempt. 463 */ 464 if (pwd && !rval && rootlogin && !rootterm(tty)) { 465 (void)printf("Login incorrect or refused on this " 466 "terminal.\n"); 467 if (hostname) 468 syslog(LOG_NOTICE, 469 "LOGIN %s REFUSED FROM %s ON TTY %s", 470 pwd->pw_name, hostname, tty); 471 else 472 syslog(LOG_NOTICE, 473 "LOGIN %s REFUSED ON TTY %s", 474 pwd->pw_name, tty); 475 continue; 476 } 477 478 if (pwd && !rval) 479 break; 480 481 (void)printf("Login incorrect or refused on this " 482 "terminal.\n"); 483 failures++; 484 cnt++; 485 /* 486 * We allow login_retries tries, but after login_backoff 487 * we start backing off. These default to 10 and 3 488 * respectively. 489 */ 490 if (cnt > login_backoff) { 491 if (cnt >= login_retries) { 492 badlogin(username); 493 sleepexit(EXIT_FAILURE); 494 } 495 sleep((u_int)((cnt - login_backoff) * 5)); 496 } 497 } 498 499 /* committed to login -- turn off timeout */ 500 (void)alarm((u_int)0); 501 502 endpwent(); 503 504 /* if user not super-user, check for disabled logins */ 505 #ifdef LOGIN_CAP 506 if (!login_getcapbool(lc, "ignorenologin", rootlogin)) 507 checknologin(login_getcapstr(lc, "nologin", NULL, NULL)); 508 #else 509 if (!rootlogin) 510 checknologin(NULL); 511 #endif 512 513 #ifdef LOGIN_CAP 514 quietlog = login_getcapbool(lc, "hushlogin", 0); 515 #else 516 quietlog = 0; 517 #endif 518 /* Temporarily give up special privileges so we can change */ 519 /* into NFS-mounted homes that are exported for non-root */ 520 /* access and have mode 7x0 */ 521 saved_uid = geteuid(); 522 saved_gid = getegid(); 523 nsaved_gids = getgroups(NGROUPS_MAX, saved_gids); 524 525 (void)setegid(pwd->pw_gid); 526 initgroups(username, pwd->pw_gid); 527 (void)seteuid(pwd->pw_uid); 528 529 if (chdir(pwd->pw_dir) < 0) { 530 #ifdef LOGIN_CAP 531 if (login_getcapbool(lc, "requirehome", 0)) { 532 (void)printf("Home directory %s required\n", 533 pwd->pw_dir); 534 sleepexit(EXIT_FAILURE); 535 } 536 #endif 537 (void)printf("No home directory %s!\n", pwd->pw_dir); 538 if (chdir("/") == -1) 539 exit(EXIT_FAILURE); 540 pwd->pw_dir = "/"; 541 (void)printf("Logging in with home = \"/\".\n"); 542 } 543 544 if (!quietlog) 545 quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0; 546 547 /* regain special privileges */ 548 (void)seteuid(saved_uid); 549 setgroups(nsaved_gids, saved_gids); 550 (void)setegid(saved_gid); 551 552 #ifdef LOGIN_CAP 553 pw_warntime = login_getcaptime(lc, "password-warn", 554 _PASSWORD_WARNDAYS * SECSPERDAY, 555 _PASSWORD_WARNDAYS * SECSPERDAY); 556 #endif 557 558 (void)gettimeofday(&now, (struct timezone *)NULL); 559 if (pwd->pw_expire) { 560 if (now.tv_sec >= pwd->pw_expire) { 561 (void)printf("Sorry -- your account has expired.\n"); 562 sleepexit(EXIT_FAILURE); 563 } else if (pwd->pw_expire - now.tv_sec < pw_warntime && 564 !quietlog) 565 (void)printf("Warning: your account expires on %s", 566 ctime(&pwd->pw_expire)); 567 } 568 if (pwd->pw_change) { 569 if (pwd->pw_change == _PASSWORD_CHGNOW) 570 need_chpass = 1; 571 else if (now.tv_sec >= pwd->pw_change) { 572 (void)printf("Sorry -- your password has expired.\n"); 573 sleepexit(EXIT_FAILURE); 574 } else if (pwd->pw_change - now.tv_sec < pw_warntime && 575 !quietlog) 576 (void)printf("Warning: your password expires on %s", 577 ctime(&pwd->pw_change)); 578 579 } 580 /* Nothing else left to fail -- really log in. */ 581 update_db(quietlog); 582 583 (void)chown(ttyn, pwd->pw_uid, 584 (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid); 585 586 if (ttyaction(ttyn, "login", pwd->pw_name)) 587 (void)printf("Warning: ttyaction failed.\n"); 588 589 #if defined(KERBEROS5) 590 /* Fork so that we can call kdestroy */ 591 if (! login_krb5_retain_ccache && has_ccache) 592 dofork(); 593 #endif 594 595 /* Destroy environment unless user has requested its preservation. */ 596 if (!pflag) 597 environ = envinit; 598 599 #ifdef LOGIN_CAP 600 if (nested == NULL && setusercontext(lc, pwd, pwd->pw_uid, 601 LOGIN_SETLOGIN) != 0) { 602 syslog(LOG_ERR, "setusercontext failed"); 603 exit(EXIT_FAILURE); 604 } 605 if (setusercontext(lc, pwd, pwd->pw_uid, 606 (LOGIN_SETALL & ~(LOGIN_SETPATH|LOGIN_SETLOGIN))) != 0) { 607 syslog(LOG_ERR, "setusercontext failed"); 608 exit(EXIT_FAILURE); 609 } 610 #else 611 (void)setgid(pwd->pw_gid); 612 613 initgroups(username, pwd->pw_gid); 614 615 if (nested == NULL && setlogin(pwd->pw_name) < 0) 616 syslog(LOG_ERR, "setlogin() failure: %m"); 617 618 /* Discard permissions last so can't get killed and drop core. */ 619 if (rootlogin) 620 (void)setuid(0); 621 else 622 (void)setuid(pwd->pw_uid); 623 #endif 624 625 if (*pwd->pw_shell == '\0') 626 pwd->pw_shell = _PATH_BSHELL; 627 #ifdef LOGIN_CAP 628 if ((shell = login_getcapstr(lc, "shell", NULL, NULL)) != NULL) { 629 if ((shell = strdup(shell)) == NULL) { 630 syslog(LOG_ERR, "Cannot alloc mem"); 631 sleepexit(EXIT_FAILURE); 632 } 633 pwd->pw_shell = shell; 634 } 635 #endif 636 637 (void)setenv("HOME", pwd->pw_dir, 1); 638 (void)setenv("SHELL", pwd->pw_shell, 1); 639 if (term[0] == '\0') { 640 char *tt = (char *)stypeof(tty); 641 #ifdef LOGIN_CAP 642 if (tt == NULL) 643 tt = login_getcapstr(lc, "term", NULL, NULL); 644 #endif 645 /* unknown term -> "su" */ 646 (void)strlcpy(term, tt != NULL ? tt : "su", sizeof(term)); 647 } 648 (void)setenv("TERM", term, 0); 649 (void)setenv("LOGNAME", pwd->pw_name, 1); 650 (void)setenv("USER", pwd->pw_name, 1); 651 652 #ifdef LOGIN_CAP 653 setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETPATH); 654 #else 655 (void)setenv("PATH", _PATH_DEFPATH, 0); 656 #endif 657 658 #ifdef KERBEROS5 659 if (krb5tkfile_env) 660 (void)setenv("KRB5CCNAME", krb5tkfile_env, 1); 661 #endif 662 663 if (tty[sizeof("tty")-1] == 'd') 664 syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name); 665 666 /* If fflag is on, assume caller/authenticator has logged root login. */ 667 if (rootlogin && fflag == 0) { 668 if (hostname) 669 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s", 670 username, tty, hostname); 671 else 672 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s", 673 username, tty); 674 } 675 676 #if defined(KERBEROS5) 677 if (KERBEROS_CONFIGURED && !quietlog && notickets == 1) 678 (void)printf("Warning: no Kerberos tickets issued.\n"); 679 #endif 680 681 if (!quietlog) { 682 char *fname; 683 #ifdef LOGIN_CAP 684 fname = login_getcapstr(lc, "copyright", NULL, NULL); 685 if (fname != NULL && access(fname, F_OK) == 0) 686 motd(fname); 687 else 688 #endif 689 (void)printf("%s", copyrightstr); 690 691 #ifdef LOGIN_CAP 692 fname = login_getcapstr(lc, "welcome", NULL, NULL); 693 if (fname == NULL || access(fname, F_OK) != 0) 694 #endif 695 fname = _PATH_MOTDFILE; 696 motd(fname); 697 698 (void)snprintf(tbuf, 699 sizeof(tbuf), "%s/%s", _PATH_MAILDIR, pwd->pw_name); 700 if (stat(tbuf, &st) == 0 && st.st_size != 0) 701 (void)printf("You have %smail.\n", 702 (st.st_mtime > st.st_atime) ? "new " : ""); 703 } 704 705 #ifdef LOGIN_CAP 706 login_close(lc); 707 #endif 708 709 (void)signal(SIGALRM, SIG_DFL); 710 (void)signal(SIGQUIT, SIG_DFL); 711 (void)signal(SIGINT, SIG_DFL); 712 (void)signal(SIGTSTP, SIG_IGN); 713 714 tbuf[0] = '-'; 715 (void)strlcpy(tbuf + 1, (p = strrchr(pwd->pw_shell, '/')) ? 716 p + 1 : pwd->pw_shell, sizeof(tbuf) - 1); 717 718 /* Wait to change password until we're unprivileged */ 719 if (need_chpass) { 720 if (!require_chpass) 721 (void)printf( 722 "Warning: your password has expired. Please change it as soon as possible.\n"); 723 else { 724 int status; 725 726 (void)printf( 727 "Your password has expired. Please choose a new one.\n"); 728 switch (fork()) { 729 case -1: 730 warn("fork"); 731 sleepexit(EXIT_FAILURE); 732 case 0: 733 execl(_PATH_BINPASSWD, "passwd", NULL); 734 _exit(EXIT_FAILURE); 735 default: 736 if (wait(&status) == -1 || 737 WEXITSTATUS(status)) 738 sleepexit(EXIT_FAILURE); 739 } 740 } 741 } 742 743 #ifdef KERBEROS5 744 if (login_krb5_get_tickets) 745 k5_write_creds(); 746 #endif 747 execlp(pwd->pw_shell, tbuf, NULL); 748 err(EXIT_FAILURE, "%s", pwd->pw_shell); 749 } 750 751 #if defined(KERBEROS5) 752 #define NBUFSIZ (MAXLOGNAME + 1 + 5) /* .root suffix */ 753 #else 754 #define NBUFSIZ (MAXLOGNAME + 1) 755 #endif 756 757 #if defined(KERBEROS5) 758 /* 759 * This routine handles cleanup stuff, and the like. 760 * It exists only in the child process. 761 */ 762 void 763 dofork(void) 764 { 765 pid_t child, wchild; 766 767 switch (child = fork()) { 768 case 0: 769 return; /* Child process */ 770 case -1: 771 err(EXIT_FAILURE, "Can't fork"); 772 /*NOTREACHED*/ 773 default: 774 break; 775 } 776 777 /* 778 * Setup stuff? This would be things we could do in parallel 779 * with login 780 */ 781 if (chdir("/") == -1) /* Let's not keep the fs busy... */ 782 err(EXIT_FAILURE, "Can't chdir to `/'"); 783 784 /* If we're the parent, watch the child until it dies */ 785 while ((wchild = wait(NULL)) != child) 786 if (wchild == -1) 787 err(EXIT_FAILURE, "Can't wait"); 788 789 /* Cleanup stuff */ 790 /* Run kdestroy to destroy tickets */ 791 if (login_krb5_get_tickets) 792 k5destroy(); 793 794 /* Leave */ 795 exit(EXIT_SUCCESS); 796 } 797 #endif 798 799 void 800 getloginname(void) 801 { 802 int ch; 803 char *p; 804 static char nbuf[NBUFSIZ]; 805 806 for (;;) { 807 (void)printf("login: "); 808 for (p = nbuf; (ch = getchar()) != '\n'; ) { 809 if (ch == EOF) { 810 badlogin(username); 811 exit(EXIT_FAILURE); 812 } 813 if (p < nbuf + (NBUFSIZ - 1)) 814 *p++ = ch; 815 } 816 if (p > nbuf) { 817 if (nbuf[0] == '-') 818 (void)fprintf(stderr, 819 "login names may not start with '-'.\n"); 820 else { 821 *p = '\0'; 822 username = nbuf; 823 break; 824 } 825 } 826 } 827 } 828 829 int 830 rootterm(char *ttyn) 831 { 832 struct ttyent *t; 833 834 return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE); 835 } 836 837 jmp_buf motdinterrupt; 838 839 void 840 motd(char *fname) 841 { 842 int fd, nchars; 843 sig_t oldint; 844 char tbuf[8192]; 845 846 if ((fd = open(fname ? fname : _PATH_MOTDFILE, O_RDONLY, 0)) < 0) 847 return; 848 oldint = signal(SIGINT, sigint); 849 if (setjmp(motdinterrupt) == 0) 850 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0) 851 (void)write(fileno(stdout), tbuf, nchars); 852 (void)signal(SIGINT, oldint); 853 (void)close(fd); 854 } 855 856 /* ARGSUSED */ 857 void 858 sigint(int signo) 859 { 860 861 longjmp(motdinterrupt, 1); 862 } 863 864 /* ARGSUSED */ 865 void 866 timedout(int signo) 867 { 868 869 (void)fprintf(stderr, "Login timed out after %d seconds\n", timeout); 870 exit(EXIT_FAILURE); 871 } 872 873 void 874 checknologin(char *fname) 875 { 876 int fd, nchars; 877 char tbuf[8192]; 878 879 if ((fd = open(fname ? fname : _PATH_NOLOGIN, O_RDONLY, 0)) >= 0) { 880 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0) 881 (void)write(fileno(stdout), tbuf, nchars); 882 sleepexit(EXIT_SUCCESS); 883 } 884 } 885 886 static void 887 update_db(int quietlog) 888 { 889 if (nested != NULL) { 890 if (hostname != NULL) 891 syslog(LOG_NOTICE, "%s to %s on tty %s from %s", 892 nested, pwd->pw_name, tty, hostname); 893 else 894 syslog(LOG_NOTICE, "%s to %s on tty %s", nested, 895 pwd->pw_name, tty); 896 897 return; 898 } 899 if (hostname != NULL && have_ss == 0) { 900 socklen_t len = sizeof(ss); 901 have_ss = getpeername(STDIN_FILENO, (struct sockaddr *)&ss, 902 &len) != -1; 903 } 904 (void)gettimeofday(&now, NULL); 905 #ifdef SUPPORT_UTMPX 906 doutmpx(); 907 dolastlogx(quietlog); 908 quietlog = 1; 909 #endif 910 #ifdef SUPPORT_UTMP 911 doutmp(); 912 dolastlog(quietlog); 913 #endif 914 } 915 916 #ifdef SUPPORT_UTMPX 917 static void 918 doutmpx(void) 919 { 920 struct utmpx utmpx; 921 char *t; 922 923 memset((void *)&utmpx, 0, sizeof(utmpx)); 924 utmpx.ut_tv = now; 925 (void)strncpy(utmpx.ut_name, username, sizeof(utmpx.ut_name)); 926 if (hostname) { 927 (void)strncpy(utmpx.ut_host, hostname, sizeof(utmpx.ut_host)); 928 utmpx.ut_ss = ss; 929 } 930 (void)strncpy(utmpx.ut_line, tty, sizeof(utmpx.ut_line)); 931 utmpx.ut_type = USER_PROCESS; 932 utmpx.ut_pid = getpid(); 933 t = tty + strlen(tty); 934 if (t - tty >= sizeof(utmpx.ut_id)) { 935 (void)strncpy(utmpx.ut_id, t - sizeof(utmpx.ut_id), 936 sizeof(utmpx.ut_id)); 937 } else { 938 (void)strncpy(utmpx.ut_id, tty, sizeof(utmpx.ut_id)); 939 } 940 if (pututxline(&utmpx) == NULL) 941 syslog(LOG_NOTICE, "Cannot update utmpx: %m"); 942 endutxent(); 943 if (updwtmpx(_PATH_WTMPX, &utmpx) != 0) 944 syslog(LOG_NOTICE, "Cannot update wtmpx: %m"); 945 } 946 947 static void 948 dolastlogx(int quiet) 949 { 950 struct lastlogx ll; 951 if (!quiet && getlastlogx(_PATH_LASTLOGX, pwd->pw_uid, &ll) != NULL) { 952 time_t t = (time_t)ll.ll_tv.tv_sec; 953 (void)printf("Last login: %.24s ", ctime(&t)); 954 if (*ll.ll_host != '\0') 955 (void)printf("from %.*s ", 956 (int)sizeof(ll.ll_host), 957 ll.ll_host); 958 (void)printf("on %.*s\n", 959 (int)sizeof(ll.ll_line), 960 ll.ll_line); 961 } 962 ll.ll_tv = now; 963 (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line)); 964 if (hostname) 965 (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host)); 966 else 967 (void)memset(ll.ll_host, '\0', sizeof(ll.ll_host)); 968 if (have_ss) 969 ll.ll_ss = ss; 970 else 971 (void)memset(&ll.ll_ss, 0, sizeof(ll.ll_ss)); 972 if (updlastlogx(_PATH_LASTLOGX, pwd->pw_uid, &ll) != 0) 973 syslog(LOG_NOTICE, "Cannot update lastlogx: %m"); 974 } 975 #endif 976 977 #ifdef SUPPORT_UTMP 978 static void 979 doutmp(void) 980 { 981 struct utmp utmp; 982 983 (void)memset((void *)&utmp, 0, sizeof(utmp)); 984 utmp.ut_time = now.tv_sec; 985 (void)strncpy(utmp.ut_name, username, sizeof(utmp.ut_name)); 986 if (hostname) 987 (void)strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host)); 988 (void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line)); 989 login(&utmp); 990 } 991 992 static void 993 dolastlog(int quiet) 994 { 995 struct lastlog ll; 996 int fd; 997 998 if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) >= 0) { 999 (void)lseek(fd, (off_t)(pwd->pw_uid * sizeof(ll)), SEEK_SET); 1000 if (!quiet) { 1001 if (read(fd, (char *)&ll, sizeof(ll)) == sizeof(ll) && 1002 ll.ll_time != 0) { 1003 (void)printf("Last login: %.24s ", 1004 ctime(&ll.ll_time)); 1005 if (*ll.ll_host != '\0') 1006 (void)printf("from %.*s ", 1007 (int)sizeof(ll.ll_host), 1008 ll.ll_host); 1009 (void)printf("on %.*s\n", 1010 (int)sizeof(ll.ll_line), ll.ll_line); 1011 } 1012 (void)lseek(fd, (off_t)(pwd->pw_uid * sizeof(ll)), 1013 SEEK_SET); 1014 } 1015 memset((void *)&ll, 0, sizeof(ll)); 1016 ll.ll_time = now.tv_sec; 1017 (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line)); 1018 if (hostname) 1019 (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host)); 1020 (void)write(fd, (char *)&ll, sizeof(ll)); 1021 (void)close(fd); 1022 } 1023 } 1024 #endif 1025 1026 void 1027 badlogin(char *name) 1028 { 1029 1030 if (failures == 0) 1031 return; 1032 if (hostname) { 1033 syslog(LOG_NOTICE, "%d LOGIN FAILURE%s FROM %s", 1034 failures, failures > 1 ? "S" : "", hostname); 1035 syslog(LOG_AUTHPRIV|LOG_NOTICE, 1036 "%d LOGIN FAILURE%s FROM %s, %s", 1037 failures, failures > 1 ? "S" : "", hostname, name); 1038 } else { 1039 syslog(LOG_NOTICE, "%d LOGIN FAILURE%s ON %s", 1040 failures, failures > 1 ? "S" : "", tty); 1041 syslog(LOG_AUTHPRIV|LOG_NOTICE, 1042 "%d LOGIN FAILURE%s ON %s, %s", 1043 failures, failures > 1 ? "S" : "", tty, name); 1044 } 1045 } 1046 1047 const char * 1048 stypeof(const char *ttyid) 1049 { 1050 struct ttyent *t; 1051 1052 return (ttyid && (t = getttynam(ttyid)) ? t->ty_type : NULL); 1053 } 1054 1055 void 1056 sleepexit(int eval) 1057 { 1058 1059 (void)sleep(5); 1060 exit(eval); 1061 } 1062 1063 void 1064 decode_ss(const char *arg) 1065 { 1066 struct sockaddr_storage *ssp; 1067 size_t len = strlen(arg); 1068 1069 if (len > sizeof(*ssp) * 4 + 1 || len < sizeof(*ssp)) 1070 errx(EXIT_FAILURE, "Bad argument"); 1071 1072 if ((ssp = malloc(len)) == NULL) 1073 err(EXIT_FAILURE, NULL); 1074 1075 if (strunvis((char *)ssp, arg) != sizeof(*ssp)) 1076 errx(EXIT_FAILURE, "Decoding error"); 1077 1078 (void)memcpy(&ss, ssp, sizeof(ss)); 1079 have_ss = 1; 1080 } 1081 1082 void 1083 usage(void) 1084 { 1085 (void)fprintf(stderr, 1086 "Usage: %s [-Ffps] [-a address] [-h hostname] [username]\n", 1087 getprogname()); 1088 exit(EXIT_FAILURE); 1089 } 1090
Indexes created Tue Sep 30 20:09:53 GMT 2025