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 1.34 1998/04/30 16:50:07 peter 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 extern void trimdomain __P((char *, int)); 122 static void usage __P((void)); 123 124 #define TTYGRPNAME "tty" /* name of group to own ttys */ 125 #define DEFAULT_BACKOFF 3 126 #define DEFAULT_RETRIES 10 127 128 /* 129 * This bounds the time given to login. Not a define so it can 130 * be patched on machines where it's too small. 131 */ 132 u_int timeout = 300; 133 134 #ifdef KERBEROS 135 int notickets = 1; 136 int noticketsdontcomplain = 1; 137 char *instance; 138 char *krbtkfile_env; 139 int authok; 140 #endif 141 142 struct passwd *pwd; 143 int failures; 144 char *term, *envinit[1], *hostname, *username, *tty; 145 char full_hostname[MAXHOSTNAMELEN]; 146 147 int 148 main(argc, argv) 149 int argc; 150 char *argv[]; 151 { 152 extern char **environ; 153 struct group *gr; 154 struct stat st; 155 struct timeval tp; 156 struct utmp utmp; 157 int rootok, retries, backoff; 158 int ask, ch, cnt, fflag, hflag, pflag, quietlog, rootlogin, rval; 159 int changepass; 160 time_t warntime; 161 uid_t uid, euid; 162 char *domain, *p, *ep, *salt, *ttyn; 163 char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10]; 164 char localhost[MAXHOSTNAMELEN]; 165 char *shell = NULL; 166 #ifdef LOGIN_CAP 167 login_cap_t *lc = NULL; 168 #ifdef LOGIN_CAP_AUTH 169 char *style, *authtype; 170 char *auth_method = NULL; 171 char *instance = NULL; 172 int authok; 173 #endif /* LOGIN_CAP_AUTH */ 174 #endif /* LOGIN_CAP */ 175 #ifdef SKEY 176 int permit_passwd = 0; 177 #endif /* SKEY */ 178 179 (void)signal(SIGALRM, timedout); 180 (void)alarm(timeout); 181 (void)signal(SIGQUIT, SIG_IGN); 182 (void)signal(SIGINT, SIG_IGN); 183 (void)setpriority(PRIO_PROCESS, 0, 0); 184 185 openlog("login", LOG_ODELAY, LOG_AUTH); 186 187 /* 188 * -p is used by getty to tell login not to destroy the environment 189 * -f is used to skip a second login authentication 190 * -h is used by other servers to pass the name of the remote 191 * host to login so that it may be placed in utmp and wtmp 192 */ 193 *full_hostname = '\0'; 194 domain = NULL; 195 term = NULL; 196 if (gethostname(localhost, sizeof(localhost)) < 0) 197 syslog(LOG_ERR, "couldn't get local hostname: %m"); 198 else 199 domain = strchr(localhost, '.'); 200 201 fflag = hflag = pflag = 0; 202 uid = getuid(); 203 euid = geteuid(); 204 while ((ch = getopt(argc, argv, "fh:p")) != -1) 205 switch (ch) { 206 case 'f': 207 fflag = 1; 208 break; 209 case 'h': 210 if (uid) 211 errx(1, "-h option: %s", strerror(EPERM)); 212 hflag = 1; 213 strncpy(full_hostname, optarg, sizeof(full_hostname)-1); 214 if (domain && (p = strchr(optarg, '.')) && 215 strcasecmp(p, domain) == 0) 216 *p = 0; 217 218 trimdomain(optarg, UT_HOSTSIZE ); 219 220 if (strlen(optarg) > UT_HOSTSIZE) { 221 struct hostent *hp = gethostbyname(optarg); 222 223 if (hp != NULL) { 224 struct in_addr in; 225 226 memmove(&in, hp->h_addr, sizeof(in)); 227 optarg = strdup(inet_ntoa(in)); 228 } else 229 optarg = "invalid hostname"; 230 } 231 hostname = optarg; 232 break; 233 case 'p': 234 pflag = 1; 235 break; 236 case '?': 237 default: 238 if (!uid) 239 syslog(LOG_ERR, "invalid flag %c", ch); 240 usage(); 241 } 242 argc -= optind; 243 argv += optind; 244 245 if (*argv) { 246 username = *argv; 247 ask = 0; 248 } else 249 ask = 1; 250 251 for (cnt = getdtablesize(); cnt > 2; cnt--) 252 (void)close(cnt); 253 254 ttyn = ttyname(STDIN_FILENO); 255 if (ttyn == NULL || *ttyn == '\0') { 256 (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY); 257 ttyn = tname; 258 } 259 if ((tty = strrchr(ttyn, '/')) != NULL) 260 ++tty; 261 else 262 tty = ttyn; 263 264 #ifdef LOGIN_CAP_AUTH 265 authtype = hostname ? "rlogin" : "login"; 266 #endif 267 #ifdef LOGIN_CAP 268 /* 269 * Get "login-retries" & "login-backoff" from default class 270 */ 271 lc = login_getclass(NULL); 272 retries = login_getcapnum(lc, "login-retries", DEFAULT_RETRIES, DEFAULT_RETRIES); 273 backoff = login_getcapnum(lc, "login-backoff", DEFAULT_BACKOFF, DEFAULT_BACKOFF); 274 login_close(lc); 275 lc = NULL; 276 #else 277 retries = DEFAULT_RETRIES; 278 backoff = DEFAULT_BACKOFF; 279 #endif 280 281 for (cnt = 0;; ask = 1) { 282 if (ask) { 283 fflag = 0; 284 getloginname(); 285 } 286 rootlogin = 0; 287 rootok = rootterm(tty); /* Default (auth may change) */ 288 #ifdef LOGIN_CAP_AUTH 289 authok = 0; 290 if (auth_method = strchr(username, ':')) { 291 *auth_method = '\0'; 292 auth_method++; 293 if (*auth_method == '\0') 294 auth_method = NULL; 295 } 296 /* 297 * We need to do this regardless of whether 298 * kerberos is available. 299 */ 300 if ((instance = strchr(username, '.')) != NULL) { 301 if (strncmp(instance, ".root", 5) == 0) 302 rootlogin = 1; 303 *instance++ = '\0'; 304 } else 305 instance = ""; 306 #else /* !LOGIN_CAP_AUTH */ 307 #ifdef KERBEROS 308 if ((instance = strchr(username, '.')) != NULL) { 309 if (strncmp(instance, ".root", 5) == 0) 310 rootlogin = 1; 311 *instance++ = '\0'; 312 } else 313 instance = ""; 314 #endif /* KERBEROS */ 315 #endif /* LOGIN_CAP_AUTH */ 316 317 if (strlen(username) > UT_NAMESIZE) 318 username[UT_NAMESIZE] = '\0'; 319 320 /* 321 * Note if trying multiple user names; log failures for 322 * previous user name, but don't bother logging one failure 323 * for nonexistent name (mistyped username). 324 */ 325 if (failures && strcmp(tbuf, username)) { 326 if (failures > (pwd ? 0 : 1)) 327 badlogin(tbuf); 328 failures = 0; 329 } 330 (void)strncpy(tbuf, username, sizeof tbuf-1); 331 tbuf[sizeof tbuf-1] = '\0'; 332 333 if ((pwd = getpwnam(username)) != NULL) 334 salt = pwd->pw_passwd; 335 else 336 salt = "xx"; 337 338 #ifdef LOGIN_CAP 339 /* 340 * Establish the class now, before we might goto 341 * within the next block. pwd can be NULL since it 342 * falls back to the "default" class if it is. 343 */ 344 if (pwd != NULL) 345 (void)seteuid(rootlogin ? 0 : pwd->pw_uid); 346 lc = login_getpwclass(pwd); 347 seteuid(euid); 348 #endif /* LOGIN_CAP */ 349 350 /* 351 * if we have a valid account name, and it doesn't have a 352 * password, or the -f option was specified and the caller 353 * is root or the caller isn't changing their uid, don't 354 * authenticate. 355 */ 356 rval = 1; 357 if (pwd != NULL) { 358 if (pwd->pw_uid == 0) 359 rootlogin = 1; 360 361 if (fflag && (uid == (uid_t)0 || 362 uid == (uid_t)pwd->pw_uid)) { 363 /* already authenticated */ 364 break; 365 } else if (pwd->pw_passwd[0] == '\0') { 366 if (!rootlogin || rootok) { 367 /* pretend password okay */ 368 rval = 0; 369 goto ttycheck; 370 } 371 } 372 } 373 374 fflag = 0; 375 376 (void)setpriority(PRIO_PROCESS, 0, -4); 377 378 #ifdef LOGIN_CAP_AUTH 379 /* 380 * This hands off authorization to an authorization program, 381 * depending on the styles available for the "auth-login", 382 * auth-rlogin (or default) authorization styles. 383 * We do this regardless of whether an account exists so that 384 * the remote user cannot tell a "real" from an invented 385 * account name. If we don't have an account we just fall 386 * back to the first method for the "default" class. 387 */ 388 if (!(style = login_getstyle(lc, auth_method, authtype))) { 389 390 /* 391 * No available authorization method 392 */ 393 rval = 1; 394 (void)printf("No auth method available for %s.\n", 395 authtype); 396 } else { 397 398 /* 399 * Put back the kerberos instance, if any was given. 400 * Don't worry about the non-kerberos case here, since 401 * if kerberos is not available or not selected and an 402 * instance is given at the login prompt, su or rlogin -l, 403 * then anything else should fail as well. 404 */ 405 if (*instance) 406 *(instance - 1) = '.'; 407 408 rval = authenticate(username, 409 lc ? lc->lc_class : "default", 410 style, authtype); 411 /* Junk it again */ 412 if (*instance) 413 *(instance - 1) = '\0'; 414 } 415 416 if (!rval) { 417 char * approvp; 418 419 /* 420 * If authentication succeeds, run any approval 421 * program, if applicable for this class. 422 */ 423 approvep = login_getcapstr(lc, "approve", NULL, NULL); 424 rval = 1; /* Assume bad login again */ 425 426 if (approvep==NULL || 427 auth_script(approvep, approvep, username, 428 lc->lc_class, 0) == 0) { 429 int r; 430 431 r = auth_scan(AUTH_OKAY); 432 /* 433 * See what the authorize program says 434 */ 435 if (r != AUTH_NONE) { 436 rval = 0; 437 438 if (!rootok && (r & AUTH_ROOTOKAY)) 439 rootok = 1; /* root approved */ 440 else 441 rootlogin = 0; 442 443 if (!authok && (r & AUTH_SECURE)) 444 authok = 1; /* secure */ 445 } 446 } 447 } 448 #else /* !LOGIN_CAP_AUTH */ 449 (void)signal(SIGINT, SIG_DFL); 450 (void)signal(SIGQUIT, SIG_DFL); 451 #ifdef SKEY 452 permit_passwd = skeyaccess(username, tty, 453 hostname ? full_hostname : NULL, 454 NULL); 455 p = skey_getpass("Password:", pwd, permit_passwd); 456 ep = skey_crypt(p, salt, pwd, permit_passwd); 457 #else /* !SKEY */ 458 p = getpass("Password:"); 459 ep = crypt(p, salt); 460 #endif/* SKEY */ 461 (void)signal(SIGINT, SIG_IGN); 462 (void)signal(SIGQUIT, SIG_IGN); 463 464 if (pwd) { 465 if (!p[0] && pwd->pw_passwd[0]) 466 ep = ":"; 467 #ifdef KERBEROS 468 #ifdef SKEY 469 /* 470 * Do not allow user to type in kerberos password 471 * over the net (actually, this is ok for encrypted 472 * links, but we have no way of determining if the 473 * link is encrypted. 474 */ 475 if (!permit_passwd) { 476 rval = 1; /* failed */ 477 } else 478 #endif /* SKEY */ 479 rval = klogin(pwd, instance, localhost, p); 480 if (rval != 0 && rootlogin && pwd->pw_uid != 0) 481 rootlogin = 0; 482 if (rval == 0) 483 authok = 1; /* kerberos authenticated ok */ 484 else if (rval == 1) /* fallback to unix passwd */ 485 rval = strcmp(ep, pwd->pw_passwd); 486 #else /* !KERBEROS */ 487 rval = strcmp(ep, pwd->pw_passwd); 488 #endif /* KERBEROS */ 489 } 490 491 /* clear entered password */ 492 memset(p, 0, strlen(p)); 493 #endif /* LOGIN_CAP_AUTH */ 494 495 (void)setpriority(PRIO_PROCESS, 0, 0); 496 497 #ifdef LOGIN_CAP_AUTH 498 if (rval) 499 auth_rmfiles(); 500 #endif 501 ttycheck: 502 /* 503 * If trying to log in as root without Kerberos, 504 * but with insecure terminal, refuse the login attempt. 505 */ 506 if (pwd && !rval) { 507 #if defined(KERBEROS) || defined(LOGIN_CAP_AUTH) 508 if (authok == 0 && rootlogin && !rootok) 509 #else 510 if (rootlogin && !rootok) 511 #endif 512 refused(NULL, "NOROOT", 0); 513 else /* valid password & authenticated */ 514 break; 515 } 516 517 (void)printf("Login incorrect\n"); 518 failures++; 519 520 /* 521 * we allow up to 'retry' (10) tries, 522 * but after 'backoff' (3) we start backing off 523 */ 524 if (++cnt > backoff) { 525 if (cnt >= retries) { 526 badlogin(username); 527 sleepexit(1); 528 } 529 sleep((u_int)((cnt - 3) * 5)); 530 } 531 } 532 533 /* committed to login -- turn off timeout */ 534 (void)alarm((u_int)0); 535 536 endpwent(); 537 538 /* if user not super-user, check for disabled logins */ 539 #ifdef LOGIN_CAP 540 if (!rootlogin) 541 auth_checknologin(lc); 542 #else 543 if (!rootlogin) 544 checknologin(); 545 #endif 546 547 #ifdef LOGIN_CAP 548 quietlog = login_getcapbool(lc, "hushlogin", 0); 549 #else 550 quietlog = 0; 551 #endif 552 (void)seteuid(rootlogin ? 0 : pwd->pw_uid); 553 if (!*pwd->pw_dir || chdir(pwd->pw_dir) < 0) { 554 #ifdef LOGIN_CAP 555 if (login_getcapbool(lc, "requirehome", 0)) 556 refused("Home directory not available", "HOMEDIR", 1); 557 #endif 558 if (chdir("/") < 0) 559 refused("Cannot find root directory", "ROOTDIR", 1); 560 pwd->pw_dir = "/"; 561 if (!quietlog || *pwd->pw_dir) 562 printf("No home directory.\nLogging in with home = \"/\".\n"); 563 } 564 (void)seteuid(euid); 565 if (!quietlog) 566 quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0; 567 568 if (pwd->pw_change || pwd->pw_expire) 569 (void)gettimeofday(&tp, (struct timezone *)NULL); 570 571 #define DEFAULT_WARN (2L * 7L * 86400L) /* Two weeks */ 572 573 #ifdef LOGIN_CAP 574 warntime = login_getcaptime(lc, "warnpassword", 575 DEFAULT_WARN, DEFAULT_WARN); 576 #else 577 warntime = DEFAULT_WARN; 578 #endif 579 580 changepass=0; 581 if (pwd->pw_change) { 582 if (tp.tv_sec >= pwd->pw_change) { 583 (void)printf("Sorry -- your password has expired.\n"); 584 changepass=1; 585 syslog(LOG_INFO, 586 "%s Password expired - forcing change", 587 pwd->pw_name); 588 } else if (pwd->pw_change - tp.tv_sec < warntime && !quietlog) 589 (void)printf("Warning: your password expires on %s", 590 ctime(&pwd->pw_change)); 591 } 592 593 #ifdef LOGIN_CAP 594 warntime = login_getcaptime(lc, "warnexpire", 595 DEFAULT_WARN, DEFAULT_WARN); 596 #else 597 warntime = DEFAULT_WARN; 598 #endif 599 600 if (pwd->pw_expire) { 601 if (tp.tv_sec >= pwd->pw_expire) { 602 refused("Sorry -- your account has expired", 603 "EXPIRED", 1); 604 } else if (pwd->pw_expire - tp.tv_sec < warntime && !quietlog) 605 (void)printf("Warning: your account expires on %s", 606 ctime(&pwd->pw_expire)); 607 } 608 609 #ifdef LOGIN_CAP 610 if (lc != NULL) { 611 if (hostname) { 612 struct hostent *hp = gethostbyname(full_hostname); 613 614 if (hp == NULL) 615 optarg = NULL; 616 else { 617 struct in_addr in; 618 memmove(&in, hp->h_addr, sizeof(in)); 619 optarg = strdup(inet_ntoa(in)); 620 } 621 if (!auth_hostok(lc, full_hostname, optarg)) 622 refused("Permission denied", "HOST", 1); 623 } 624 625 if (!auth_ttyok(lc, tty)) 626 refused("Permission denied", "TTY", 1); 627 628 if (!auth_timeok(lc, time(NULL))) 629 refused("Logins not available right now", "TIME", 1); 630 } 631 shell=login_getcapstr(lc, "shell", pwd->pw_shell, pwd->pw_shell); 632 #else /* !LOGIN_CAP */ 633 shell=pwd->pw_shell; 634 #endif /* LOGIN_CAP */ 635 if (*pwd->pw_shell == '\0') 636 pwd->pw_shell = _PATH_BSHELL; 637 if (*shell == '\0') /* Not overridden */ 638 shell = pwd->pw_shell; 639 if ((shell = strdup(shell)) == NULL) { 640 syslog(LOG_NOTICE, "memory allocation error"); 641 sleepexit(1); 642 } 643 644 #ifdef LOGIN_ACCESS 645 if (login_access(pwd->pw_name, hostname ? full_hostname : tty) == 0) 646 refused("Permission denied", "ACCESS", 1); 647 #endif /* LOGIN_ACCESS */ 648 649 /* Nothing else left to fail -- really log in. */ 650 memset((void *)&utmp, 0, sizeof(utmp)); 651 (void)time(&utmp.ut_time); 652 (void)strncpy(utmp.ut_name, username, sizeof(utmp.ut_name)); 653 if (hostname) 654 (void)strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host)); 655 (void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line)); 656 login(&utmp); 657 658 dolastlog(quietlog); 659 660 /* 661 * Set device protections, depending on what terminal the 662 * user is logged in. This feature is used on Suns to give 663 * console users better privacy. 664 */ 665 login_fbtab(tty, pwd->pw_uid, pwd->pw_gid); 666 667 (void)chown(ttyn, pwd->pw_uid, 668 (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid); 669 670 /* 671 * Preserve TERM if it happens to be already set. 672 */ 673 if ((term = getenv("TERM")) != NULL) 674 term = strdup(term); 675 676 /* 677 * Exclude cons/vt/ptys only, assume dialup otherwise 678 * TODO: Make dialup tty determination a library call 679 * for consistency (finger etc.) 680 */ 681 if (hostname==NULL && isdialuptty(tty)) 682 syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name); 683 684 #ifdef KERBEROS 685 if (!quietlog && notickets == 1 && !noticketsdontcomplain) 686 (void)printf("Warning: no Kerberos tickets issued.\n"); 687 #endif 688 689 #ifdef LOGALL 690 /* 691 * Syslog each successful login, so we don't have to watch hundreds 692 * of wtmp or lastlogin files. 693 */ 694 if (hostname) 695 syslog(LOG_INFO, "login from %s on %s as %s", 696 full_hostname, tty, pwd->pw_name); 697 else 698 syslog(LOG_INFO, "login on %s as %s", 699 tty, pwd->pw_name); 700 #endif 701 702 /* 703 * If fflag is on, assume caller/authenticator has logged root login. 704 */ 705 if (rootlogin && fflag == 0) 706 { 707 if (hostname) 708 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s", 709 username, tty, full_hostname); 710 else 711 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s", 712 username, tty); 713 } 714 715 /* 716 * Destroy environment unless user has requested its preservation. 717 * We need to do this before setusercontext() because that may 718 * set or reset some environment variables. 719 */ 720 if (!pflag) 721 environ = envinit; 722 723 /* 724 * We don't need to be root anymore, so 725 * set the user and session context 726 */ 727 #ifdef LOGIN_CAP 728 if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETALL) != 0) { 729 syslog(LOG_ERR, "setusercontext() failed - exiting"); 730 exit(1); 731 } 732 #else 733 if (setlogin(pwd->pw_name) < 0) 734 syslog(LOG_ERR, "setlogin() failure: %m"); 735 736 (void)setgid(pwd->pw_gid); 737 initgroups(username, pwd->pw_gid); 738 (void)setuid(rootlogin ? 0 : pwd->pw_uid); 739 #endif 740 741 (void)setenv("SHELL", pwd->pw_shell, 1); 742 (void)setenv("HOME", pwd->pw_dir, 1); 743 if (term != NULL && *term != '\0') 744 (void)setenv("TERM", term, 1); /* Preset overrides */ 745 else { 746 (void)setenv("TERM", stypeof(tty), 0); /* Fallback doesn't */ 747 } 748 (void)setenv("LOGNAME", pwd->pw_name, 1); 749 (void)setenv("USER", pwd->pw_name, 1); 750 (void)setenv("PATH", rootlogin ? _PATH_STDPATH : _PATH_DEFPATH, 0); 751 #ifdef KERBEROS 752 if (krbtkfile_env) 753 (void)setenv("KRBTKFILE", krbtkfile_env, 1); 754 #endif 755 #if LOGIN_CAP_AUTH 756 auth_env(); 757 #endif 758 759 #ifdef LOGIN_CAP 760 if (!quietlog) { 761 char *cw; 762 763 cw = login_getcapstr(lc, "copyright", NULL, NULL); 764 if (cw != NULL && access(cw, F_OK) == 0) 765 motd(cw); 766 else 767 (void)printf("%s\n\t%s %s\n", 768 "Copyright (c) 1980, 1983, 1986, 1988, 1990, 1991, 1993, 1994", 769 "The Regents of the University of California. ", 770 "All rights reserved."); 771 772 (void)printf("\n"); 773 774 cw = login_getcapstr(lc, "welcome", NULL, NULL); 775 if (cw == NULL || access(cw, F_OK) != 0) 776 cw = _PATH_MOTDFILE; 777 motd(cw); 778 779 cw = getenv("MAIL"); /* $MAIL may have been set by class */ 780 if (cw != NULL) { 781 strncpy(tbuf, cw, sizeof(tbuf)); 782 tbuf[sizeof(tbuf)-1] = '\0'; 783 } else 784 snprintf(tbuf, sizeof(tbuf), "%s/%s", 785 _PATH_MAILDIR, pwd->pw_name); 786 #else 787 if (!quietlog) { 788 (void)printf("%s\n\t%s %s\n", 789 "Copyright (c) 1980, 1983, 1986, 1988, 1990, 1991, 1993, 1994", 790 "The Regents of the University of California. ", 791 "All rights reserved."); 792 motd(_PATH_MOTDFILE); 793 snprintf(tbuf, sizeof(tbuf), "%s/%s", 794 _PATH_MAILDIR, pwd->pw_name); 795 #endif 796 if (stat(tbuf, &st) == 0 && st.st_size != 0) 797 (void)printf("You have %smail.\n", 798 (st.st_mtime > st.st_atime) ? "new " : ""); 799 } 800 801 #ifdef LOGIN_CAP 802 login_close(lc); 803 #endif 804 805 (void)signal(SIGALRM, SIG_DFL); 806 (void)signal(SIGQUIT, SIG_DFL); 807 (void)signal(SIGINT, SIG_DFL); 808 (void)signal(SIGTSTP, SIG_IGN); 809 810 if (changepass) { 811 if (system(_PATH_CHPASS) != 0) 812 sleepexit(1); 813 } 814 815 /* 816 * Login shells have a leading '-' in front of argv[0] 817 */ 818 tbuf[0] = '-'; 819 (void)strcpy(tbuf + 1, (p = strrchr(pwd->pw_shell, '/')) ? p + 1 : pwd->pw_shell); 820 821 execlp(shell, tbuf, 0); 822 err(1, "%s", shell); 823 } 824 825 static void 826 usage() 827 { 828 (void)fprintf(stderr, "usage: login [-fp] [-h hostname] [username]\n"); 829 exit(1); 830 } 831 832 /* 833 * Allow for authentication style and/or kerberos instance 834 * */ 835 836 #define NBUFSIZ UT_NAMESIZE + 64 837 838 void 839 getloginname() 840 { 841 int ch; 842 char *p; 843 static char nbuf[NBUFSIZ]; 844 845 for (;;) { 846 (void)printf("login: "); 847 for (p = nbuf; (ch = getchar()) != '\n'; ) { 848 if (ch == EOF) { 849 badlogin(username); 850 exit(0); 851 } 852 if (p < nbuf + (NBUFSIZ - 1)) 853 *p++ = ch; 854 } 855 if (p > nbuf) 856 if (nbuf[0] == '-') 857 (void)fprintf(stderr, 858 "login names may not start with '-'.\n"); 859 else { 860 *p = '\0'; 861 username = nbuf; 862 break; 863 } 864 } 865 } 866 867 int 868 rootterm(ttyn) 869 char *ttyn; 870 { 871 struct ttyent *t; 872 873 return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE); 874 } 875 876 volatile int motdinterrupt; 877 878 /* ARGSUSED */ 879 void 880 sigint(signo) 881 int signo; 882 { 883 motdinterrupt = 1; 884 } 885 886 void 887 motd(motdfile) 888 char *motdfile; 889 { 890 int fd, nchars; 891 sig_t oldint; 892 char tbuf[256]; 893 894 if ((fd = open(motdfile, O_RDONLY, 0)) < 0) 895 return; 896 motdinterrupt = 0; 897 oldint = signal(SIGINT, sigint); 898 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0 && !motdinterrupt) 899 (void)write(fileno(stdout), tbuf, nchars); 900 (void)signal(SIGINT, oldint); 901 (void)close(fd); 902 } 903 904 /* ARGSUSED */ 905 void 906 timedout(signo) 907 int signo; 908 { 909 (void)fprintf(stderr, "Login timed out after %d seconds\n", timeout); 910 exit(0); 911 } 912 913 #ifndef LOGIN_CAP 914 void 915 checknologin() 916 { 917 int fd, nchars; 918 char tbuf[8192]; 919 920 if ((fd = open(_PATH_NOLOGIN, O_RDONLY, 0)) >= 0) { 921 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0) 922 (void)write(fileno(stdout), tbuf, nchars); 923 sleepexit(0); 924 } 925 } 926 #endif 927 928 void 929 dolastlog(quiet) 930 int quiet; 931 { 932 struct lastlog ll; 933 int fd; 934 935 if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) >= 0) { 936 (void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), L_SET); 937 if (!quiet) { 938 if (read(fd, (char *)&ll, sizeof(ll)) == sizeof(ll) && 939 ll.ll_time != 0) { 940 (void)printf("Last login: %.*s ", 941 24-5, (char *)ctime(&ll.ll_time)); 942 if (*ll.ll_host != '\0') 943 (void)printf("from %.*s\n", 944 (int)sizeof(ll.ll_host), 945 ll.ll_host); 946 else 947 (void)printf("on %.*s\n", 948 (int)sizeof(ll.ll_line), 949 ll.ll_line); 950 } 951 (void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), L_SET); 952 } 953 memset((void *)&ll, 0, sizeof(ll)); 954 (void)time(&ll.ll_time); 955 (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line)); 956 if (hostname) 957 (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host)); 958 (void)write(fd, (char *)&ll, sizeof(ll)); 959 (void)close(fd); 960 } 961 } 962 963 void 964 badlogin(name) 965 char *name; 966 { 967 968 if (failures == 0) 969 return; 970 if (hostname) { 971 syslog(LOG_NOTICE, "%d LOGIN FAILURE%s FROM %s", 972 failures, failures > 1 ? "S" : "", full_hostname); 973 syslog(LOG_AUTHPRIV|LOG_NOTICE, 974 "%d LOGIN FAILURE%s FROM %s, %s", 975 failures, failures > 1 ? "S" : "", full_hostname, name); 976 } else { 977 syslog(LOG_NOTICE, "%d LOGIN FAILURE%s ON %s", 978 failures, failures > 1 ? "S" : "", tty); 979 syslog(LOG_AUTHPRIV|LOG_NOTICE, 980 "%d LOGIN FAILURE%s ON %s, %s", 981 failures, failures > 1 ? "S" : "", tty, name); 982 } 983 } 984 985 #undef UNKNOWN 986 #define UNKNOWN "su" 987 988 char * 989 stypeof(ttyid) 990 char *ttyid; 991 { 992 993 struct ttyent *t; 994 995 return (ttyid && (t = getttynam(ttyid)) ? t->ty_type : UNKNOWN); 996 } 997 998 void 999 refused(msg, rtype, lout) 1000 char *msg; 1001 char *rtype; 1002 int lout; 1003 { 1004 1005 if (msg != NULL) 1006 printf("%s.\n", msg); 1007 if (hostname) 1008 syslog(LOG_NOTICE, "LOGIN %s REFUSED (%s) FROM %s ON TTY %s", 1009 pwd->pw_name, rtype, full_hostname, tty); 1010 else 1011 syslog(LOG_NOTICE, "LOGIN %s REFUSED (%s) ON TTY %s", 1012 pwd->pw_name, rtype, tty); 1013 if (lout) 1014 sleepexit(1); 1015 } 1016 1017 void 1018 sleepexit(eval) 1019 int eval; 1020 { 1021 1022 (void)sleep(5); 1023 exit(eval); 1024 } 1025