1 /*- 2 * Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #if 0 35 static char copyright[] = 36 "@(#) Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38 #endif 39 40 #ifndef lint 41 #if 0 42 static char sccsid[] = "@(#)login.c 8.4 (Berkeley) 4/2/94"; 43 #endif 44 static const char rcsid[] = 45 "$Id: login.c,v 1.31 1998/02/05 18:37:02 guido Exp $"; 46 #endif /* not lint */ 47 48 /* 49 * login [ name ] 50 * login -h hostname (for telnetd, etc.) 51 * login -f name (for pre-authenticated login: datakit, xterm, etc.) 52 */ 53 54 #include <sys/copyright.h> 55 #include <sys/param.h> 56 #include <sys/stat.h> 57 #include <sys/time.h> 58 #include <sys/resource.h> 59 #include <sys/file.h> 60 #include <netinet/in.h> 61 #include <arpa/inet.h> 62 63 #include <err.h> 64 #include <errno.h> 65 #include <grp.h> 66 #include <netdb.h> 67 #include <pwd.h> 68 #include <setjmp.h> 69 #include <signal.h> 70 #include <stdio.h> 71 #include <stdlib.h> 72 #include <string.h> 73 #include <syslog.h> 74 #include <ttyent.h> 75 #include <unistd.h> 76 #include <utmp.h> 77 78 #ifdef LOGIN_CAP 79 #include <login_cap.h> 80 #else /* Undef AUTH as well */ 81 #undef LOGIN_CAP_AUTH 82 #endif 83 84 /* 85 * If LOGIN_CAP_AUTH is activated: 86 * kerberose & skey logins are runtime selected via login 87 * login_getstyle() and authentication types for login classes 88 * The actual login itself is handled via /usr/libexec/login_<style> 89 * Valid styles are determined by the auth-type=style,style entries 90 * in the login class. 91 */ 92 #ifdef LOGIN_CAP_AUTH 93 #undef KERBEROS 94 #undef SKEY 95 #endif /* LOGIN_CAP_AUTH */ 96 97 #ifdef SKEY 98 #include <skey.h> 99 #endif /* SKEY */ 100 101 #include "pathnames.h" 102 103 void badlogin __P((char *)); 104 void checknologin __P((void)); 105 void dolastlog __P((int)); 106 void getloginname __P((void)); 107 void motd __P((char *)); 108 int rootterm __P((char *)); 109 void sigint __P((int)); 110 void sleepexit __P((int)); 111 void refused __P((char *,char *,int)); 112 char *stypeof __P((char *)); 113 void timedout __P((int)); 114 int login_access __P((char *, char *)); 115 void login_fbtab __P((char *, uid_t, gid_t)); 116 #ifdef KERBEROS 117 int klogin __P((struct passwd *, char *, char *, char *)); 118 #endif 119 120 extern void login __P((struct utmp *)); 121 static void usage __P((void)); 122 123 #define TTYGRPNAME "tty" /* name of group to own ttys */ 124 #define DEFAULT_BACKOFF 3 125 #define DEFAULT_RETRIES 10 126 127 /* 128 * This bounds the time given to login. Not a define so it can 129 * be patched on machines where it's too small. 130 */ 131 u_int timeout = 300; 132 133 #ifdef KERBEROS 134 int notickets = 1; 135 int noticketsdontcomplain = 1; 136 char *instance; 137 char *krbtkfile_env; 138 int authok; 139 #endif 140 141 struct passwd *pwd; 142 int failures; 143 char *term, *envinit[1], *hostname, *username, *tty; 144 char full_hostname[MAXHOSTNAMELEN]; 145 146 int 147 main(argc, argv) 148 int argc; 149 char *argv[]; 150 { 151 extern char **environ; 152 struct group *gr; 153 struct stat st; 154 struct timeval tp; 155 struct utmp utmp; 156 int rootok, retries, backoff; 157 int ask, ch, cnt, fflag, hflag, pflag, quietlog, rootlogin, rval; 158 int changepass; 159 time_t warntime; 160 uid_t uid; 161 char *domain, *p, *ep, *salt, *ttyn; 162 char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10]; 163 char localhost[MAXHOSTNAMELEN]; 164 char *shell = NULL; 165 #ifdef LOGIN_CAP 166 login_cap_t *lc = NULL; 167 #ifdef LOGIN_CAP_AUTH 168 char *style, *authtype; 169 char *auth_method = NULL; 170 char *instance = NULL; 171 int authok; 172 #endif /* LOGIN_CAP_AUTH */ 173 #endif /* LOGIN_CAP */ 174 #ifdef SKEY 175 int permit_passwd = 0; 176 #endif /* SKEY */ 177 178 (void)signal(SIGALRM, timedout); 179 (void)alarm(timeout); 180 (void)signal(SIGQUIT, SIG_IGN); 181 (void)signal(SIGINT, SIG_IGN); 182 (void)setpriority(PRIO_PROCESS, 0, 0); 183 184 openlog("login", LOG_ODELAY, LOG_AUTH); 185 186 /* 187 * -p is used by getty to tell login not to destroy the environment 188 * -f is used to skip a second login authentication 189 * -h is used by other servers to pass the name of the remote 190 * host to login so that it may be placed in utmp and wtmp 191 */ 192 *full_hostname = '\0'; 193 domain = NULL; 194 term = NULL; 195 if (gethostname(localhost, sizeof(localhost)) < 0) 196 syslog(LOG_ERR, "couldn't get local hostname: %m"); 197 else 198 domain = strchr(localhost, '.'); 199 200 fflag = hflag = pflag = 0; 201 uid = getuid(); 202 while ((ch = getopt(argc, argv, "fh:p")) != -1) 203 switch (ch) { 204 case 'f': 205 fflag = 1; 206 break; 207 case 'h': 208 if (uid) 209 errx(1, "-h option: %s", strerror(EPERM)); 210 hflag = 1; 211 strncpy(full_hostname, optarg, sizeof(full_hostname)-1); 212 if (domain && (p = strchr(optarg, '.')) && 213 strcasecmp(p, domain) == 0) 214 *p = 0; 215 if (strlen(optarg) > UT_HOSTSIZE) { 216 struct hostent *hp = gethostbyname(optarg); 217 218 if (hp != NULL) { 219 struct in_addr in; 220 221 memmove(&in, hp->h_addr, sizeof(in)); 222 optarg = strdup(inet_ntoa(in)); 223 } else 224 optarg = "invalid hostname"; 225 } 226 hostname = optarg; 227 break; 228 case 'p': 229 pflag = 1; 230 break; 231 case '?': 232 default: 233 if (!uid) 234 syslog(LOG_ERR, "invalid flag %c", ch); 235 usage(); 236 } 237 argc -= optind; 238 argv += optind; 239 240 if (*argv) { 241 username = *argv; 242 ask = 0; 243 } else 244 ask = 1; 245 246 for (cnt = getdtablesize(); cnt > 2; cnt--) 247 (void)close(cnt); 248 249 ttyn = ttyname(STDIN_FILENO); 250 if (ttyn == NULL || *ttyn == '\0') { 251 (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY); 252 ttyn = tname; 253 } 254 if ((tty = strrchr(ttyn, '/')) != NULL) 255 ++tty; 256 else 257 tty = ttyn; 258 259 #ifdef LOGIN_CAP_AUTH 260 authtype = hostname ? "rlogin" : "login"; 261 #endif 262 #ifdef LOGIN_CAP 263 /* 264 * Get "login-retries" & "login-backoff" from default class 265 */ 266 lc = login_getclass(NULL); 267 retries = login_getcapnum(lc, "login-retries", DEFAULT_RETRIES, DEFAULT_RETRIES); 268 backoff = login_getcapnum(lc, "login-backoff", DEFAULT_BACKOFF, DEFAULT_BACKOFF); 269 login_close(lc); 270 lc = NULL; 271 #else 272 retries = DEFAULT_RETRIES; 273 backoff = DEFAULT_BACKOFF; 274 #endif 275 276 for (cnt = 0;; ask = 1) { 277 if (ask) { 278 fflag = 0; 279 getloginname(); 280 } 281 rootlogin = 0; 282 rootok = rootterm(tty); /* Default (auth may change) */ 283 #ifdef LOGIN_CAP_AUTH 284 authok = 0; 285 if (auth_method = strchr(username, ':')) { 286 *auth_method = '\0'; 287 auth_method++; 288 if (*auth_method == '\0') 289 auth_method = NULL; 290 } 291 /* 292 * We need to do this regardless of whether 293 * kerberos is available. 294 */ 295 if ((instance = strchr(username, '.')) != NULL) { 296 if (strncmp(instance, ".root", 5) == 0) 297 rootlogin = 1; 298 *instance++ = '\0'; 299 } else 300 instance = ""; 301 #else /* !LOGIN_CAP_AUTH */ 302 #ifdef KERBEROS 303 if ((instance = strchr(username, '.')) != NULL) { 304 if (strncmp(instance, ".root", 5) == 0) 305 rootlogin = 1; 306 *instance++ = '\0'; 307 } else 308 instance = ""; 309 #endif /* KERBEROS */ 310 #endif /* LOGIN_CAP_AUTH */ 311 312 if (strlen(username) > UT_NAMESIZE) 313 username[UT_NAMESIZE] = '\0'; 314 315 /* 316 * Note if trying multiple user names; log failures for 317 * previous user name, but don't bother logging one failure 318 * for nonexistent name (mistyped username). 319 */ 320 if (failures && strcmp(tbuf, username)) { 321 if (failures > (pwd ? 0 : 1)) 322 badlogin(tbuf); 323 failures = 0; 324 } 325 (void)strncpy(tbuf, username, sizeof tbuf-1); 326 tbuf[sizeof tbuf-1] = '\0'; 327 328 if ((pwd = getpwnam(username)) != NULL) 329 salt = pwd->pw_passwd; 330 else 331 salt = "xx"; 332 333 #ifdef LOGIN_CAP 334 /* 335 * Establish the class now, before we might goto 336 * within the next block. pwd can be NULL since it 337 * falls back to the "default" class if it is. 338 */ 339 lc = login_getpwclass(pwd); 340 #endif /* LOGIN_CAP */ 341 342 /* 343 * if we have a valid account name, and it doesn't have a 344 * password, or the -f option was specified and the caller 345 * is root or the caller isn't changing their uid, don't 346 * authenticate. 347 */ 348 rval = 1; 349 if (pwd != NULL) { 350 if (pwd->pw_uid == 0) 351 rootlogin = 1; 352 353 if (fflag && (uid == (uid_t)0 || 354 uid == (uid_t)pwd->pw_uid)) { 355 /* already authenticated */ 356 break; 357 } else if (pwd->pw_passwd[0] == '\0') { 358 if (!rootlogin || rootok) { 359 /* pretend password okay */ 360 rval = 0; 361 goto ttycheck; 362 } 363 } 364 } 365 366 fflag = 0; 367 368 (void)setpriority(PRIO_PROCESS, 0, -4); 369 370 #ifdef LOGIN_CAP_AUTH 371 /* 372 * This hands off authorization to an authorization program, 373 * depending on the styles available for the "auth-login", 374 * auth-rlogin (or default) authorization styles. 375 * We do this regardless of whether an account exists so that 376 * the remote user cannot tell a "real" from an invented 377 * account name. If we don't have an account we just fall 378 * back to the first method for the "default" class. 379 */ 380 if (!(style = login_getstyle(lc, auth_method, authtype))) { 381 382 /* 383 * No available authorization method 384 */ 385 rval = 1; 386 (void)printf("No auth method available for %s.\n", 387 authtype); 388 } else { 389 390 /* 391 * Put back the kerberos instance, if any was given. 392 * Don't worry about the non-kerberos case here, since 393 * if kerberos is not available or not selected and an 394 * instance is given at the login prompt, su or rlogin -l, 395 * then anything else should fail as well. 396 */ 397 if (*instance) 398 *(instance - 1) = '.'; 399 400 rval = authenticate(username, 401 lc ? lc->lc_class : "default", 402 style, authtype); 403 /* Junk it again */ 404 if (*instance) 405 *(instance - 1) = '\0'; 406 } 407 408 if (!rval) { 409 char * approvp; 410 411 /* 412 * If authentication succeeds, run any approval 413 * program, if applicable for this class. 414 */ 415 approvep = login_getcapstr(lc, "approve", NULL, NULL); 416 rval = 1; /* Assume bad login again */ 417 418 if (approvep==NULL || 419 auth_script(approvep, approvep, username, 420 lc->lc_class, 0) == 0) { 421 int r; 422 423 r = auth_scan(AUTH_OKAY); 424 /* 425 * See what the authorize program says 426 */ 427 if (r != AUTH_NONE) { 428 rval = 0; 429 430 if (!rootok && (r & AUTH_ROOTOKAY)) 431 rootok = 1; /* root approved */ 432 else 433 rootlogin = 0; 434 435 if (!authok && (r & AUTH_SECURE)) 436 authok = 1; /* secure */ 437 } 438 } 439 } 440 #else /* !LOGIN_CAP_AUTH */ 441 (void)signal(SIGINT, SIG_DFL); 442 (void)signal(SIGQUIT, SIG_DFL); 443 #ifdef SKEY 444 permit_passwd = skeyaccess(username, tty, 445 hostname ? full_hostname : NULL, 446 NULL); 447 p = skey_getpass("Password:", pwd, permit_passwd); 448 ep = skey_crypt(p, salt, pwd, permit_passwd); 449 #else /* !SKEY */ 450 p = getpass("Password:"); 451 ep = crypt(p, salt); 452 #endif/* SKEY */ 453 (void)signal(SIGINT, SIG_IGN); 454 (void)signal(SIGQUIT, SIG_IGN); 455 456 if (pwd) { 457 if (!p[0] && pwd->pw_passwd[0]) 458 ep = ":"; 459 #ifdef KERBEROS 460 #ifdef SKEY 461 /* 462 * Do not allow user to type in kerberos password 463 * over the net (actually, this is ok for encrypted 464 * links, but we have no way of determining if the 465 * link is encrypted. 466 */ 467 if (!permit_passwd) { 468 rval = 1; /* failed */ 469 } else 470 #endif /* SKEY */ 471 rval = klogin(pwd, instance, localhost, p); 472 if (rval != 0 && rootlogin && pwd->pw_uid != 0) 473 rootlogin = 0; 474 if (rval == 0) 475 authok = 1; /* kerberos authenticated ok */ 476 else if (rval == 1) /* fallback to unix passwd */ 477 rval = strcmp(ep, pwd->pw_passwd); 478 #else /* !KERBEROS */ 479 rval = strcmp(ep, pwd->pw_passwd); 480 #endif /* KERBEROS */ 481 } 482 483 /* clear entered password */ 484 memset(p, 0, strlen(p)); 485 #endif /* LOGIN_CAP_AUTH */ 486 487 (void)setpriority(PRIO_PROCESS, 0, 0); 488 489 #ifdef LOGIN_CAP_AUTH 490 if (rval) 491 auth_rmfiles(); 492 #endif 493 ttycheck: 494 /* 495 * If trying to log in as root without Kerberos, 496 * but with insecure terminal, refuse the login attempt. 497 */ 498 if (pwd && !rval) { 499 #if defined(KERBEROS) || defined(LOGIN_CAP_AUTH) 500 if (authok == 0 && rootlogin && !rootok) 501 #else 502 if (rootlogin && !rootok) 503 #endif 504 refused(NULL, "NOROOT", 0); 505 else /* valid password & authenticated */ 506 break; 507 } 508 509 (void)printf("Login incorrect\n"); 510 failures++; 511 512 /* 513 * we allow up to 'retry' (10) tries, 514 * but after 'backoff' (3) we start backing off 515 */ 516 if (++cnt > backoff) { 517 if (cnt >= retries) { 518 badlogin(username); 519 sleepexit(1); 520 } 521 sleep((u_int)((cnt - 3) * 5)); 522 } 523 } 524 525 /* committed to login -- turn off timeout */ 526 (void)alarm((u_int)0); 527 528 endpwent(); 529 530 /* if user not super-user, check for disabled logins */ 531 #ifdef LOGIN_CAP 532 if (!rootlogin) 533 auth_checknologin(lc); 534 #else 535 if (!rootlogin) 536 checknologin(); 537 #endif 538 539 #ifdef LOGIN_CAP 540 quietlog = login_getcapbool(lc, "hushlogin", 0); 541 #else 542 quietlog = 0; 543 #endif 544 if (!*pwd->pw_dir || chdir(pwd->pw_dir) < 0) { 545 #ifdef LOGIN_CAP 546 if (login_getcapbool(lc, "requirehome", 0)) 547 refused("Home directory not available", "HOMEDIR", 1); 548 #endif 549 if (chdir("/") < 0) 550 refused("Cannot find root directory", "ROOTDIR", 1); 551 pwd->pw_dir = "/"; 552 if (!quietlog || *pwd->pw_dir) 553 printf("No home directory.\nLogging in with home = \"/\".\n"); 554 } 555 if (!quietlog) 556 quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0; 557 558 if (pwd->pw_change || pwd->pw_expire) 559 (void)gettimeofday(&tp, (struct timezone *)NULL); 560 561 #define DEFAULT_WARN (2L * 7L * 86400L) /* Two weeks */ 562 563 #ifdef LOGIN_CAP 564 warntime = login_getcaptime(lc, "warnpassword", 565 DEFAULT_WARN, DEFAULT_WARN); 566 #else 567 warntime = DEFAULT_WARN; 568 #endif 569 570 changepass=0; 571 if (pwd->pw_change) { 572 if (tp.tv_sec >= pwd->pw_change) { 573 (void)printf("Sorry -- your password has expired.\n"); 574 changepass=1; 575 syslog(LOG_INFO, 576 "%s Password expired - forcing change", 577 pwd->pw_name); 578 } else if (pwd->pw_change - tp.tv_sec < warntime && !quietlog) 579 (void)printf("Warning: your password expires on %s", 580 ctime(&pwd->pw_change)); 581 } 582 583 #ifdef LOGIN_CAP 584 warntime = login_getcaptime(lc, "warnexpire", 585 DEFAULT_WARN, DEFAULT_WARN); 586 #else 587 warntime = DEFAULT_WARN; 588 #endif 589 590 if (pwd->pw_expire) { 591 if (tp.tv_sec >= pwd->pw_expire) { 592 refused("Sorry -- your account has expired", 593 "EXPIRED", 1); 594 } else if (pwd->pw_expire - tp.tv_sec < warntime && !quietlog) 595 (void)printf("Warning: your account expires on %s", 596 ctime(&pwd->pw_expire)); 597 } 598 599 #ifdef LOGIN_CAP 600 if (lc != NULL) { 601 if (hostname) { 602 struct hostent *hp = gethostbyname(full_hostname); 603 604 if (hp == NULL) 605 optarg = NULL; 606 else { 607 struct in_addr in; 608 memmove(&in, hp->h_addr, sizeof(in)); 609 optarg = strdup(inet_ntoa(in)); 610 } 611 if (!auth_hostok(lc, full_hostname, optarg)) 612 refused("Permission denied", "HOST", 1); 613 } 614 615 if (!auth_ttyok(lc, tty)) 616 refused("Permission denied", "TTY", 1); 617 618 if (!auth_timeok(lc, time(NULL))) 619 refused("Logins not available right now", "TIME", 1); 620 } 621 shell=login_getcapstr(lc, "shell", pwd->pw_shell, pwd->pw_shell); 622 #else /* !LOGIN_CAP */ 623 shell=pwd->pw_shell; 624 #endif /* LOGIN_CAP */ 625 if (*pwd->pw_shell == '\0') 626 pwd->pw_shell = _PATH_BSHELL; 627 if (*shell == '\0') /* Not overridden */ 628 shell = pwd->pw_shell; 629 if ((shell = strdup(shell)) == NULL) { 630 syslog(LOG_NOTICE, "memory allocation error"); 631 sleepexit(1); 632 } 633 634 #ifdef LOGIN_ACCESS 635 if (login_access(pwd->pw_name, hostname ? full_hostname : tty) == 0) 636 refused("Permission denied", "ACCESS", 1); 637 #endif /* LOGIN_ACCESS */ 638 639 /* Nothing else left to fail -- really log in. */ 640 memset((void *)&utmp, 0, sizeof(utmp)); 641 (void)time(&utmp.ut_time); 642 (void)strncpy(utmp.ut_name, username, sizeof(utmp.ut_name)); 643 if (hostname) 644 (void)strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host)); 645 (void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line)); 646 login(&utmp); 647 648 dolastlog(quietlog); 649 650 /* 651 * Set device protections, depending on what terminal the 652 * user is logged in. This feature is used on Suns to give 653 * console users better privacy. 654 */ 655 login_fbtab(tty, pwd->pw_uid, pwd->pw_gid); 656 657 (void)chown(ttyn, pwd->pw_uid, 658 (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid); 659 660 /* 661 * Preserve TERM if it happens to be already set. 662 */ 663 if ((term = getenv("TERM")) != NULL) 664 term = strdup(term); 665 666 /* 667 * Exclude cons/vt/ptys only, assume dialup otherwise 668 * TODO: Make dialup tty determination a library call 669 * for consistency (finger etc.) 670 */ 671 if (hostname==NULL && isdialuptty(tty)) 672 syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name); 673 674 #ifdef KERBEROS 675 if (!quietlog && notickets == 1 && !noticketsdontcomplain) 676 (void)printf("Warning: no Kerberos tickets issued.\n"); 677 #endif 678 679 #ifdef LOGALL 680 /* 681 * Syslog each successful login, so we don't have to watch hundreds 682 * of wtmp or lastlogin files. 683 */ 684 if (hostname) 685 syslog(LOG_INFO, "login from %s on %s as %s", 686 full_hostname, tty, pwd->pw_name); 687 else 688 syslog(LOG_INFO, "login on %s as %s", 689 tty, pwd->pw_name); 690 #endif 691 692 /* 693 * If fflag is on, assume caller/authenticator has logged root login. 694 */ 695 if (rootlogin && fflag == 0) 696 { 697 if (hostname) 698 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s", 699 username, tty, full_hostname); 700 else 701 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s", 702 username, tty); 703 } 704 705 /* 706 * Destroy environment unless user has requested its preservation. 707 * We need to do this before setusercontext() because that may 708 * set or reset some environment variables. 709 */ 710 if (!pflag) 711 environ = envinit; 712 713 /* 714 * We don't need to be root anymore, so 715 * set the user and session context 716 */ 717 #ifdef LOGIN_CAP 718 if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETALL) != 0) { 719 syslog(LOG_ERR, "setusercontext() failed - exiting"); 720 exit(1); 721 } 722 #else 723 if (setlogin(pwd->pw_name) < 0) 724 syslog(LOG_ERR, "setlogin() failure: %m"); 725 726 (void)setgid(pwd->pw_gid); 727 initgroups(username, pwd->pw_gid); 728 (void)setuid(rootlogin ? 0 : pwd->pw_uid); 729 #endif 730 731 (void)setenv("SHELL", pwd->pw_shell, 1); 732 (void)setenv("HOME", pwd->pw_dir, 1); 733 if (term != NULL && *term != '\0') 734 (void)setenv("TERM", term, 1); /* Preset overrides */ 735 else { 736 (void)setenv("TERM", stypeof(tty), 0); /* Fallback doesn't */ 737 } 738 (void)setenv("LOGNAME", pwd->pw_name, 1); 739 (void)setenv("USER", pwd->pw_name, 1); 740 (void)setenv("PATH", rootlogin ? _PATH_STDPATH : _PATH_DEFPATH, 0); 741 #ifdef KERBEROS 742 if (krbtkfile_env) 743 (void)setenv("KRBTKFILE", krbtkfile_env, 1); 744 #endif 745 #if LOGIN_CAP_AUTH 746 auth_env(); 747 #endif 748 749 #ifdef LOGIN_CAP 750 if (!quietlog) { 751 char *cw; 752 753 cw = login_getcapstr(lc, "copyright", NULL, NULL); 754 if (cw != NULL && access(cw, F_OK) == 0) 755 motd(cw); 756 else 757 (void)printf("%s\n\t%s %s\n", 758 "Copyright (c) 1980, 1983, 1986, 1988, 1990, 1991, 1993, 1994", 759 "The Regents of the University of California. ", 760 "All rights reserved."); 761 762 (void)printf("\n"); 763 764 cw = login_getcapstr(lc, "welcome", NULL, NULL); 765 if (cw == NULL || access(cw, F_OK) != 0) 766 cw = _PATH_MOTDFILE; 767 motd(cw); 768 769 cw = getenv("MAIL"); /* $MAIL may have been set by class */ 770 if (cw != NULL) { 771 strncpy(tbuf, cw, sizeof(tbuf)); 772 tbuf[sizeof(tbuf)-1] = '\0'; 773 } else 774 snprintf(tbuf, sizeof(tbuf), "%s/%s", 775 _PATH_MAILDIR, pwd->pw_name); 776 #else 777 if (!quietlog) { 778 (void)printf("%s\n\t%s %s\n", 779 "Copyright (c) 1980, 1983, 1986, 1988, 1990, 1991, 1993, 1994", 780 "The Regents of the University of California. ", 781 "All rights reserved."); 782 motd(_PATH_MOTDFILE); 783 snprintf(tbuf, sizeof(tbuf), "%s/%s", 784 _PATH_MAILDIR, pwd->pw_name); 785 #endif 786 if (stat(tbuf, &st) == 0 && st.st_size != 0) 787 (void)printf("You have %smail.\n", 788 (st.st_mtime > st.st_atime) ? "new " : ""); 789 } 790 791 #ifdef LOGIN_CAP 792 login_close(lc); 793 #endif 794 795 (void)signal(SIGALRM, SIG_DFL); 796 (void)signal(SIGQUIT, SIG_DFL); 797 (void)signal(SIGINT, SIG_DFL); 798 (void)signal(SIGTSTP, SIG_IGN); 799 800 if (changepass) { 801 if (system(_PATH_CHPASS) != 0) 802 sleepexit(1); 803 } 804 805 /* 806 * Login shells have a leading '-' in front of argv[0] 807 */ 808 tbuf[0] = '-'; 809 (void)strcpy(tbuf + 1, (p = strrchr(pwd->pw_shell, '/')) ? p + 1 : pwd->pw_shell); 810 811 execlp(shell, tbuf, 0); 812 err(1, "%s", shell); 813 } 814 815 static void 816 usage() 817 { 818 (void)fprintf(stderr, "usage: login [-fp] [-h hostname] [username]\n"); 819 exit(1); 820 } 821 822 /* 823 * Allow for authentication style and/or kerberos instance 824 * */ 825 826 #define NBUFSIZ UT_NAMESIZE + 64 827 828 void 829 getloginname() 830 { 831 int ch; 832 char *p; 833 static char nbuf[NBUFSIZ]; 834 835 for (;;) { 836 (void)printf("login: "); 837 for (p = nbuf; (ch = getchar()) != '\n'; ) { 838 if (ch == EOF) { 839 badlogin(username); 840 exit(0); 841 } 842 if (p < nbuf + (NBUFSIZ - 1)) 843 *p++ = ch; 844 } 845 if (p > nbuf) 846 if (nbuf[0] == '-') 847 (void)fprintf(stderr, 848 "login names may not start with '-'.\n"); 849 else { 850 *p = '\0'; 851 username = nbuf; 852 break; 853 } 854 } 855 } 856 857 int 858 rootterm(ttyn) 859 char *ttyn; 860 { 861 struct ttyent *t; 862 863 return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE); 864 } 865 866 volatile int motdinterrupt; 867 868 /* ARGSUSED */ 869 void 870 sigint(signo) 871 int signo; 872 { 873 motdinterrupt = 1; 874 } 875 876 void 877 motd(motdfile) 878 char *motdfile; 879 { 880 int fd, nchars; 881 sig_t oldint; 882 char tbuf[256]; 883 884 if ((fd = open(motdfile, O_RDONLY, 0)) < 0) 885 return; 886 motdinterrupt = 0; 887 oldint = signal(SIGINT, sigint); 888 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0 && !motdinterrupt) 889 (void)write(fileno(stdout), tbuf, nchars); 890 (void)signal(SIGINT, oldint); 891 (void)close(fd); 892 } 893 894 /* ARGSUSED */ 895 void 896 timedout(signo) 897 int signo; 898 { 899 (void)fprintf(stderr, "Login timed out after %d seconds\n", timeout); 900 exit(0); 901 } 902 903 #ifndef LOGIN_CAP 904 void 905 checknologin() 906 { 907 int fd, nchars; 908 char tbuf[8192]; 909 910 if ((fd = open(_PATH_NOLOGIN, O_RDONLY, 0)) >= 0) { 911 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0) 912 (void)write(fileno(stdout), tbuf, nchars); 913 sleepexit(0); 914 } 915 } 916 #endif 917 918 void 919 dolastlog(quiet) 920 int quiet; 921 { 922 struct lastlog ll; 923 int fd; 924 925 if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) >= 0) { 926 (void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), L_SET); 927 if (!quiet) { 928 if (read(fd, (char *)&ll, sizeof(ll)) == sizeof(ll) && 929 ll.ll_time != 0) { 930 (void)printf("Last login: %.*s ", 931 24-5, (char *)ctime(&ll.ll_time)); 932 if (*ll.ll_host != '\0') 933 (void)printf("from %.*s\n", 934 (int)sizeof(ll.ll_host), 935 ll.ll_host); 936 else 937 (void)printf("on %.*s\n", 938 (int)sizeof(ll.ll_line), 939 ll.ll_line); 940 } 941 (void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), L_SET); 942 } 943 memset((void *)&ll, 0, sizeof(ll)); 944 (void)time(&ll.ll_time); 945 (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line)); 946 if (hostname) 947 (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host)); 948 (void)write(fd, (char *)&ll, sizeof(ll)); 949 (void)close(fd); 950 } 951 } 952 953 void 954 badlogin(name) 955 char *name; 956 { 957 958 if (failures == 0) 959 return; 960 if (hostname) { 961 syslog(LOG_NOTICE, "%d LOGIN FAILURE%s FROM %s", 962 failures, failures > 1 ? "S" : "", full_hostname); 963 syslog(LOG_AUTHPRIV|LOG_NOTICE, 964 "%d LOGIN FAILURE%s FROM %s, %s", 965 failures, failures > 1 ? "S" : "", full_hostname, name); 966 } else { 967 syslog(LOG_NOTICE, "%d LOGIN FAILURE%s ON %s", 968 failures, failures > 1 ? "S" : "", tty); 969 syslog(LOG_AUTHPRIV|LOG_NOTICE, 970 "%d LOGIN FAILURE%s ON %s, %s", 971 failures, failures > 1 ? "S" : "", tty, name); 972 } 973 } 974 975 #undef UNKNOWN 976 #define UNKNOWN "su" 977 978 char * 979 stypeof(ttyid) 980 char *ttyid; 981 { 982 983 struct ttyent *t; 984 985 return (ttyid && (t = getttynam(ttyid)) ? t->ty_type : UNKNOWN); 986 } 987 988 void 989 refused(msg, rtype, lout) 990 char *msg; 991 char *rtype; 992 int lout; 993 { 994 995 if (msg != NULL) 996 printf("%s.\n", msg); 997 if (hostname) 998 syslog(LOG_NOTICE, "LOGIN %s REFUSED (%s) FROM %s ON TTY %s", 999 pwd->pw_name, rtype, full_hostname, tty); 1000 else 1001 syslog(LOG_NOTICE, "LOGIN %s REFUSED (%s) ON TTY %s", 1002 pwd->pw_name, rtype, tty); 1003 if (lout) 1004 sleepexit(1); 1005 } 1006 1007 void 1008 sleepexit(eval) 1009 int eval; 1010 { 1011 1012 (void)sleep(5); 1013 exit(eval); 1014 } 1015