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 "$FreeBSD$"; 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/socket.h> 58 #include <sys/time.h> 59 #include <sys/resource.h> 60 #include <sys/file.h> 61 #include <netinet/in.h> 62 #include <arpa/inet.h> 63 64 #include <err.h> 65 #include <errno.h> 66 #include <grp.h> 67 #include <libutil.h> 68 #include <login_cap.h> 69 #include <netdb.h> 70 #include <pwd.h> 71 #include <setjmp.h> 72 #include <signal.h> 73 #include <stdio.h> 74 #include <stdlib.h> 75 #include <string.h> 76 #include <syslog.h> 77 #include <ttyent.h> 78 #include <unistd.h> 79 #include <utmp.h> 80 81 #ifndef NO_PAM 82 #include <security/pam_appl.h> 83 #include <security/pam_misc.h> 84 #endif 85 86 #include "pathnames.h" 87 88 /* wrapper for KAME-special getnameinfo() */ 89 #ifndef NI_WITHSCOPEID 90 #define NI_WITHSCOPEID 0 91 #endif 92 93 void badlogin __P((char *)); 94 void checknologin __P((void)); 95 void dolastlog __P((int)); 96 void getloginname __P((void)); 97 void motd __P((char *)); 98 int rootterm __P((char *)); 99 void sigint __P((int)); 100 void sleepexit __P((int)); 101 void refused __P((char *,char *,int)); 102 char *stypeof __P((char *)); 103 void timedout __P((int)); 104 int login_access __P((char *, char *)); 105 void login_fbtab __P((char *, uid_t, gid_t)); 106 107 #ifndef NO_PAM 108 static int auth_pam __P((void)); 109 #endif 110 static int auth_traditional __P((void)); 111 extern void login __P((struct utmp *)); 112 static void usage __P((void)); 113 114 #define TTYGRPNAME "tty" /* name of group to own ttys */ 115 #define DEFAULT_BACKOFF 3 116 #define DEFAULT_RETRIES 10 117 118 /* 119 * This bounds the time given to login. Not a define so it can 120 * be patched on machines where it's too small. 121 */ 122 u_int timeout = 300; 123 124 /* Buffer for signal handling of timeout */ 125 jmp_buf timeout_buf; 126 127 struct passwd *pwd; 128 int failures; 129 char *term, *envinit[1], *hostname, *username, *tty; 130 char full_hostname[MAXHOSTNAMELEN]; 131 132 int 133 main(argc, argv) 134 int argc; 135 char *argv[]; 136 { 137 extern char **environ; 138 struct group *gr; 139 struct stat st; 140 struct timeval tp; 141 struct utmp utmp; 142 int rootok, retries, backoff; 143 int ask, ch, cnt, fflag, hflag, pflag, quietlog, rootlogin, rval; 144 int changepass; 145 time_t warntime; 146 uid_t uid, euid; 147 gid_t egid; 148 char *p, *ttyn; 149 char tbuf[MAXPATHLEN + 2]; 150 char tname[sizeof(_PATH_TTY) + 10]; 151 char *shell = NULL; 152 login_cap_t *lc = NULL; 153 154 (void)signal(SIGQUIT, SIG_IGN); 155 (void)signal(SIGINT, SIG_IGN); 156 if (setjmp(timeout_buf)) { 157 if (failures) 158 badlogin(tbuf); 159 (void)fprintf(stderr, 160 "Login timed out after %d seconds\n", timeout); 161 exit(0); 162 } 163 (void)signal(SIGALRM, timedout); 164 (void)alarm(timeout); 165 (void)setpriority(PRIO_PROCESS, 0, 0); 166 167 openlog("login", LOG_ODELAY, LOG_AUTH); 168 169 /* 170 * -p is used by getty to tell login not to destroy the environment 171 * -f is used to skip a second login authentication 172 * -h is used by other servers to pass the name of the remote 173 * host to login so that it may be placed in utmp and wtmp 174 */ 175 *full_hostname = '\0'; 176 term = NULL; 177 178 fflag = hflag = pflag = 0; 179 uid = getuid(); 180 euid = geteuid(); 181 egid = getegid(); 182 while ((ch = getopt(argc, argv, "fh:p")) != -1) 183 switch (ch) { 184 case 'f': 185 fflag = 1; 186 break; 187 case 'h': 188 if (uid) 189 errx(1, "-h option: %s", strerror(EPERM)); 190 hflag = 1; 191 strncpy(full_hostname, optarg, sizeof(full_hostname)-1); 192 193 trimdomain(optarg, UT_HOSTSIZE); 194 195 if (strlen(optarg) > UT_HOSTSIZE) { 196 struct addrinfo hints, *res; 197 int ga_err; 198 199 memset(&hints, 0, sizeof(hints)); 200 hints.ai_family = AF_UNSPEC; 201 ga_err = getaddrinfo(optarg, NULL, &hints, 202 &res); 203 if (ga_err == 0) { 204 char hostbuf[MAXHOSTNAMELEN]; 205 206 getnameinfo(res->ai_addr, 207 res->ai_addrlen, 208 hostbuf, 209 sizeof(hostbuf), NULL, 0, 210 NI_NUMERICHOST| 211 NI_WITHSCOPEID); 212 optarg = strdup(hostbuf); 213 } else 214 optarg = "invalid hostname"; 215 if (res != NULL) 216 freeaddrinfo(res); 217 } 218 hostname = optarg; 219 break; 220 case 'p': 221 pflag = 1; 222 break; 223 case '?': 224 default: 225 if (!uid) 226 syslog(LOG_ERR, "invalid flag %c", ch); 227 usage(); 228 } 229 argc -= optind; 230 argv += optind; 231 232 if (*argv) { 233 username = *argv; 234 ask = 0; 235 } else 236 ask = 1; 237 238 for (cnt = getdtablesize(); cnt > 2; cnt--) 239 (void)close(cnt); 240 241 ttyn = ttyname(STDIN_FILENO); 242 if (ttyn == NULL || *ttyn == '\0') { 243 (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY); 244 ttyn = tname; 245 } 246 if ((tty = strrchr(ttyn, '/')) != NULL) 247 ++tty; 248 else 249 tty = ttyn; 250 251 /* 252 * Get "login-retries" & "login-backoff" from default class 253 */ 254 lc = login_getclass(NULL); 255 retries = login_getcapnum(lc, "login-retries", DEFAULT_RETRIES, DEFAULT_RETRIES); 256 backoff = login_getcapnum(lc, "login-backoff", DEFAULT_BACKOFF, DEFAULT_BACKOFF); 257 login_close(lc); 258 lc = NULL; 259 260 for (cnt = 0;; ask = 1) { 261 if (ask) { 262 fflag = 0; 263 getloginname(); 264 } 265 rootlogin = 0; 266 rootok = rootterm(tty); /* Default (auth may change) */ 267 268 if (strlen(username) > UT_NAMESIZE) 269 username[UT_NAMESIZE] = '\0'; 270 271 /* 272 * Note if trying multiple user names; log failures for 273 * previous user name, but don't bother logging one failure 274 * for nonexistent name (mistyped username). 275 */ 276 if (failures && strcmp(tbuf, username)) { 277 if (failures > (pwd ? 0 : 1)) 278 badlogin(tbuf); 279 } 280 (void)strncpy(tbuf, username, sizeof tbuf-1); 281 tbuf[sizeof tbuf-1] = '\0'; 282 283 pwd = getpwnam(username); 284 285 /* 286 * if we have a valid account name, and it doesn't have a 287 * password, or the -f option was specified and the caller 288 * is root or the caller isn't changing their uid, don't 289 * authenticate. 290 */ 291 if (pwd != NULL) { 292 if (pwd->pw_uid == 0) 293 rootlogin = 1; 294 295 if (fflag && (uid == (uid_t)0 || 296 uid == (uid_t)pwd->pw_uid)) { 297 /* already authenticated */ 298 break; 299 } else if (pwd->pw_passwd[0] == '\0') { 300 if (!rootlogin || rootok) { 301 /* pretend password okay */ 302 rval = 0; 303 goto ttycheck; 304 } 305 } 306 } 307 308 fflag = 0; 309 310 (void)setpriority(PRIO_PROCESS, 0, -4); 311 312 #ifndef NO_PAM 313 /* 314 * Try to authenticate using PAM. If a PAM system error 315 * occurs, perhaps because of a botched configuration, 316 * then fall back to using traditional Unix authentication. 317 */ 318 if ((rval = auth_pam()) == -1) 319 #endif /* NO_PAM */ 320 rval = auth_traditional(); 321 322 (void)setpriority(PRIO_PROCESS, 0, 0); 323 324 #ifndef NO_PAM 325 /* 326 * PAM authentication may have changed "pwd" to the 327 * entry for the template user. Check again to see if 328 * this is a root login after all. 329 */ 330 if (pwd != NULL && pwd->pw_uid == 0) 331 rootlogin = 1; 332 #endif /* NO_PAM */ 333 334 ttycheck: 335 /* 336 * If trying to log in as root without Kerberos, 337 * but with insecure terminal, refuse the login attempt. 338 */ 339 if (pwd && !rval) { 340 if (rootlogin && !rootok) 341 refused(NULL, "NOROOT", 0); 342 else /* valid password & authenticated */ 343 break; 344 } 345 346 (void)printf("Login incorrect\n"); 347 failures++; 348 349 /* 350 * we allow up to 'retry' (10) tries, 351 * but after 'backoff' (3) we start backing off 352 */ 353 if (++cnt > backoff) { 354 if (cnt >= retries) { 355 badlogin(username); 356 sleepexit(1); 357 } 358 sleep((u_int)((cnt - backoff) * 5)); 359 } 360 } 361 362 /* committed to login -- turn off timeout */ 363 (void)alarm((u_int)0); 364 365 endpwent(); 366 367 /* 368 * Establish the login class. 369 */ 370 lc = login_getpwclass(pwd); 371 372 /* if user not super-user, check for disabled logins */ 373 if (!rootlogin) 374 auth_checknologin(lc); 375 376 quietlog = login_getcapbool(lc, "hushlogin", 0); 377 /* Switching needed for NFS with root access disabled */ 378 (void)setegid(pwd->pw_gid); 379 (void)seteuid(rootlogin ? 0 : pwd->pw_uid); 380 if (!*pwd->pw_dir || chdir(pwd->pw_dir) < 0) { 381 if (login_getcapbool(lc, "requirehome", 0)) 382 refused("Home directory not available", "HOMEDIR", 1); 383 if (chdir("/") < 0) 384 refused("Cannot find root directory", "ROOTDIR", 1); 385 if (!quietlog || *pwd->pw_dir) 386 printf("No home directory.\nLogging in with home = \"/\".\n"); 387 pwd->pw_dir = "/"; 388 } 389 (void)seteuid(euid); 390 (void)setegid(egid); 391 if (!quietlog) 392 quietlog = access(_PATH_HUSHLOGIN, F_OK) == 0; 393 394 if (pwd->pw_change || pwd->pw_expire) 395 (void)gettimeofday(&tp, (struct timezone *)NULL); 396 397 #define DEFAULT_WARN (2L * 7L * 86400L) /* Two weeks */ 398 399 warntime = login_getcaptime(lc, "warnpassword", 400 DEFAULT_WARN, DEFAULT_WARN); 401 402 changepass=0; 403 if (pwd->pw_change) { 404 if (tp.tv_sec >= pwd->pw_change) { 405 (void)printf("Sorry -- your password has expired.\n"); 406 changepass=1; 407 syslog(LOG_INFO, 408 "%s Password expired - forcing change", 409 pwd->pw_name); 410 } else if (pwd->pw_change - tp.tv_sec < warntime && !quietlog) 411 (void)printf("Warning: your password expires on %s", 412 ctime(&pwd->pw_change)); 413 } 414 415 warntime = login_getcaptime(lc, "warnexpire", 416 DEFAULT_WARN, DEFAULT_WARN); 417 418 if (pwd->pw_expire) { 419 if (tp.tv_sec >= pwd->pw_expire) { 420 refused("Sorry -- your account has expired", 421 "EXPIRED", 1); 422 } else if (pwd->pw_expire - tp.tv_sec < warntime && !quietlog) 423 (void)printf("Warning: your account expires on %s", 424 ctime(&pwd->pw_expire)); 425 } 426 427 if (lc != NULL) { 428 if (hostname) { 429 struct addrinfo hints, *res; 430 int ga_err; 431 432 memset(&hints, 0, sizeof(hints)); 433 hints.ai_family = AF_UNSPEC; 434 ga_err = getaddrinfo(full_hostname, NULL, &hints, 435 &res); 436 if (ga_err == 0) { 437 char hostbuf[MAXHOSTNAMELEN]; 438 439 getnameinfo(res->ai_addr, res->ai_addrlen, 440 hostbuf, sizeof(hostbuf), NULL, 0, 441 NI_NUMERICHOST|NI_WITHSCOPEID); 442 optarg = strdup(hostbuf); 443 } else 444 optarg = NULL; 445 if (res != NULL) 446 freeaddrinfo(res); 447 if (!auth_hostok(lc, full_hostname, optarg)) 448 refused("Permission denied", "HOST", 1); 449 } 450 451 if (!auth_ttyok(lc, tty)) 452 refused("Permission denied", "TTY", 1); 453 454 if (!auth_timeok(lc, time(NULL))) 455 refused("Logins not available right now", "TIME", 1); 456 } 457 shell=login_getcapstr(lc, "shell", pwd->pw_shell, pwd->pw_shell); 458 if (*pwd->pw_shell == '\0') 459 pwd->pw_shell = _PATH_BSHELL; 460 if (*shell == '\0') /* Not overridden */ 461 shell = pwd->pw_shell; 462 if ((shell = strdup(shell)) == NULL) { 463 syslog(LOG_NOTICE, "memory allocation error"); 464 sleepexit(1); 465 } 466 467 #ifdef LOGIN_ACCESS 468 if (login_access(pwd->pw_name, hostname ? full_hostname : tty) == 0) 469 refused("Permission denied", "ACCESS", 1); 470 #endif /* LOGIN_ACCESS */ 471 472 /* Nothing else left to fail -- really log in. */ 473 memset((void *)&utmp, 0, sizeof(utmp)); 474 (void)time(&utmp.ut_time); 475 (void)strncpy(utmp.ut_name, username, sizeof(utmp.ut_name)); 476 if (hostname) 477 (void)strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host)); 478 (void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line)); 479 login(&utmp); 480 481 dolastlog(quietlog); 482 483 /* 484 * Set device protections, depending on what terminal the 485 * user is logged in. This feature is used on Suns to give 486 * console users better privacy. 487 */ 488 login_fbtab(tty, pwd->pw_uid, pwd->pw_gid); 489 490 /* 491 * Clear flags of the tty. None should be set, and when the 492 * user sets them otherwise, this can cause the chown to fail. 493 * Since it isn't clear that flags are useful on character 494 * devices, we just clear them. 495 */ 496 if (chflags(ttyn, 0) && errno != EOPNOTSUPP) 497 syslog(LOG_ERR, "chmod(%s): %m", ttyn); 498 if (chown(ttyn, pwd->pw_uid, 499 (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid)) 500 syslog(LOG_ERR, "chmod(%s): %m", ttyn); 501 502 503 /* 504 * Preserve TERM if it happens to be already set. 505 */ 506 if ((term = getenv("TERM")) != NULL) 507 term = strdup(term); 508 509 /* 510 * Exclude cons/vt/ptys only, assume dialup otherwise 511 * TODO: Make dialup tty determination a library call 512 * for consistency (finger etc.) 513 */ 514 if (hostname==NULL && isdialuptty(tty)) 515 syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name); 516 517 #ifdef LOGALL 518 /* 519 * Syslog each successful login, so we don't have to watch hundreds 520 * of wtmp or lastlogin files. 521 */ 522 if (hostname) 523 syslog(LOG_INFO, "login from %s on %s as %s", 524 full_hostname, tty, pwd->pw_name); 525 else 526 syslog(LOG_INFO, "login on %s as %s", 527 tty, pwd->pw_name); 528 #endif 529 530 /* 531 * If fflag is on, assume caller/authenticator has logged root login. 532 */ 533 if (rootlogin && fflag == 0) 534 { 535 if (hostname) 536 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s", 537 username, tty, full_hostname); 538 else 539 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s", 540 username, tty); 541 } 542 543 /* 544 * Destroy environment unless user has requested its preservation. 545 * We need to do this before setusercontext() because that may 546 * set or reset some environment variables. 547 */ 548 if (!pflag) 549 environ = envinit; 550 551 /* 552 * We don't need to be root anymore, so 553 * set the user and session context 554 */ 555 if (setlogin(username) != 0) { 556 syslog(LOG_ERR, "setlogin(%s): %m - exiting", username); 557 exit(1); 558 } 559 if (setusercontext(lc, pwd, pwd->pw_uid, 560 LOGIN_SETALL & ~LOGIN_SETLOGIN) != 0) { 561 syslog(LOG_ERR, "setusercontext() failed - exiting"); 562 exit(1); 563 } 564 565 (void)setenv("SHELL", pwd->pw_shell, 1); 566 (void)setenv("HOME", pwd->pw_dir, 1); 567 if (term != NULL && *term != '\0') 568 (void)setenv("TERM", term, 1); /* Preset overrides */ 569 else { 570 (void)setenv("TERM", stypeof(tty), 0); /* Fallback doesn't */ 571 } 572 (void)setenv("LOGNAME", username, 1); 573 (void)setenv("USER", username, 1); 574 (void)setenv("PATH", rootlogin ? _PATH_STDPATH : _PATH_DEFPATH, 0); 575 576 if (!quietlog) { 577 char *cw; 578 579 cw = login_getcapstr(lc, "copyright", NULL, NULL); 580 if (cw != NULL && access(cw, F_OK) == 0) 581 motd(cw); 582 else 583 (void)printf("%s\n\t%s %s\n", 584 "Copyright (c) 1980, 1983, 1986, 1988, 1990, 1991, 1993, 1994", 585 "The Regents of the University of California. ", 586 "All rights reserved."); 587 588 (void)printf("\n"); 589 590 cw = login_getcapstr(lc, "welcome", NULL, NULL); 591 if (cw == NULL || access(cw, F_OK) != 0) 592 cw = _PATH_MOTDFILE; 593 motd(cw); 594 595 cw = getenv("MAIL"); /* $MAIL may have been set by class */ 596 if (cw != NULL) { 597 strncpy(tbuf, cw, sizeof(tbuf)); 598 tbuf[sizeof(tbuf)-1] = '\0'; 599 } else 600 snprintf(tbuf, sizeof(tbuf), "%s/%s", 601 _PATH_MAILDIR, pwd->pw_name); 602 if (stat(tbuf, &st) == 0 && st.st_size != 0) 603 (void)printf("You have %smail.\n", 604 (st.st_mtime > st.st_atime) ? "new " : ""); 605 } 606 607 login_close(lc); 608 609 (void)signal(SIGALRM, SIG_DFL); 610 (void)signal(SIGQUIT, SIG_DFL); 611 (void)signal(SIGINT, SIG_DFL); 612 (void)signal(SIGTSTP, SIG_IGN); 613 614 if (changepass) { 615 if (system(_PATH_CHPASS) != 0) 616 sleepexit(1); 617 } 618 619 /* 620 * Login shells have a leading '-' in front of argv[0] 621 */ 622 tbuf[0] = '-'; 623 (void)strcpy(tbuf + 1, (p = strrchr(pwd->pw_shell, '/')) ? p + 1 : pwd->pw_shell); 624 625 execlp(shell, tbuf, 0); 626 err(1, "%s", shell); 627 } 628 629 static int 630 auth_traditional() 631 { 632 int rval; 633 char *p; 634 char *ep; 635 char *salt; 636 637 rval = 1; 638 salt = pwd != NULL ? pwd->pw_passwd : "xx"; 639 640 p = getpass("Password:"); 641 ep = crypt(p, salt); 642 643 if (pwd) { 644 if (!p[0] && pwd->pw_passwd[0]) 645 ep = ":"; 646 if (strcmp(ep, pwd->pw_passwd) == 0) 647 rval = 0; 648 } 649 650 /* clear entered password */ 651 memset(p, 0, strlen(p)); 652 return rval; 653 } 654 655 #ifndef NO_PAM 656 /* 657 * Attempt to authenticate the user using PAM. Returns 0 if the user is 658 * authenticated, or 1 if not authenticated. If some sort of PAM system 659 * error occurs (e.g., the "/etc/pam.conf" file is missing) then this 660 * function returns -1. This can be used as an indication that we should 661 * fall back to a different authentication mechanism. 662 */ 663 static int 664 auth_pam() 665 { 666 pam_handle_t *pamh = NULL; 667 const char *tmpl_user; 668 const void *item; 669 int rval; 670 int e; 671 static struct pam_conv conv = { misc_conv, NULL }; 672 673 if ((e = pam_start("login", username, &conv, &pamh)) != PAM_SUCCESS) { 674 syslog(LOG_ERR, "pam_start: %s", pam_strerror(pamh, e)); 675 return -1; 676 } 677 if ((e = pam_set_item(pamh, PAM_TTY, tty)) != PAM_SUCCESS) { 678 syslog(LOG_ERR, "pam_set_item(PAM_TTY): %s", 679 pam_strerror(pamh, e)); 680 return -1; 681 } 682 if (hostname != NULL && 683 (e = pam_set_item(pamh, PAM_RHOST, full_hostname)) != PAM_SUCCESS) { 684 syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s", 685 pam_strerror(pamh, e)); 686 return -1; 687 } 688 e = pam_authenticate(pamh, 0); 689 switch (e) { 690 691 case PAM_SUCCESS: 692 /* 693 * With PAM we support the concept of a "template" 694 * user. The user enters a login name which is 695 * authenticated by PAM, usually via a remote service 696 * such as RADIUS or TACACS+. If authentication 697 * succeeds, a different but related "template" name 698 * is used for setting the credentials, shell, and 699 * home directory. The name the user enters need only 700 * exist on the remote authentication server, but the 701 * template name must be present in the local password 702 * database. 703 * 704 * This is supported by two various mechanisms in the 705 * individual modules. However, from the application's 706 * point of view, the template user is always passed 707 * back as a changed value of the PAM_USER item. 708 */ 709 if ((e = pam_get_item(pamh, PAM_USER, &item)) == 710 PAM_SUCCESS) { 711 tmpl_user = (const char *) item; 712 if (strcmp(username, tmpl_user) != 0) 713 pwd = getpwnam(tmpl_user); 714 } else 715 syslog(LOG_ERR, "Couldn't get PAM_USER: %s", 716 pam_strerror(pamh, e)); 717 if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != 718 PAM_SUCCESS) 719 syslog(LOG_ERR, "Couldn't establish credentials: %s", 720 pam_strerror(pamh, e)); 721 rval = 0; 722 break; 723 724 case PAM_AUTH_ERR: 725 case PAM_USER_UNKNOWN: 726 case PAM_MAXTRIES: 727 rval = 1; 728 break; 729 730 default: 731 syslog(LOG_ERR, "auth_pam: %s", pam_strerror(pamh, e)); 732 rval = -1; 733 break; 734 } 735 if ((e = pam_end(pamh, e)) != PAM_SUCCESS) { 736 syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e)); 737 rval = -1; 738 } 739 return rval; 740 } 741 #endif /* NO_PAM */ 742 743 static void 744 usage() 745 { 746 (void)fprintf(stderr, "usage: login [-fp] [-h hostname] [username]\n"); 747 exit(1); 748 } 749 750 /* 751 * Allow for authentication style and/or kerberos instance 752 * */ 753 754 #define NBUFSIZ UT_NAMESIZE + 64 755 756 void 757 getloginname() 758 { 759 int ch; 760 char *p; 761 static char nbuf[NBUFSIZ]; 762 763 for (;;) { 764 (void)printf("login: "); 765 for (p = nbuf; (ch = getchar()) != '\n'; ) { 766 if (ch == EOF) { 767 badlogin(username); 768 exit(0); 769 } 770 if (p < nbuf + (NBUFSIZ - 1)) 771 *p++ = ch; 772 } 773 if (p > nbuf) { 774 if (nbuf[0] == '-') 775 (void)fprintf(stderr, 776 "login names may not start with '-'.\n"); 777 else { 778 *p = '\0'; 779 username = nbuf; 780 break; 781 } 782 } 783 } 784 } 785 786 int 787 rootterm(ttyn) 788 char *ttyn; 789 { 790 struct ttyent *t; 791 792 return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE); 793 } 794 795 volatile int motdinterrupt; 796 797 /* ARGSUSED */ 798 void 799 sigint(signo) 800 int signo; 801 { 802 motdinterrupt = 1; 803 } 804 805 void 806 motd(motdfile) 807 char *motdfile; 808 { 809 int fd, nchars; 810 sig_t oldint; 811 char tbuf[256]; 812 813 if ((fd = open(motdfile, O_RDONLY, 0)) < 0) 814 return; 815 motdinterrupt = 0; 816 oldint = signal(SIGINT, sigint); 817 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0 && !motdinterrupt) 818 (void)write(fileno(stdout), tbuf, nchars); 819 (void)signal(SIGINT, oldint); 820 (void)close(fd); 821 } 822 823 /* ARGSUSED */ 824 void 825 timedout(signo) 826 int signo; 827 { 828 longjmp(timeout_buf, signo); 829 } 830 831 832 void 833 dolastlog(quiet) 834 int quiet; 835 { 836 struct lastlog ll; 837 int fd; 838 839 if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) >= 0) { 840 (void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), L_SET); 841 if (!quiet) { 842 if (read(fd, (char *)&ll, sizeof(ll)) == sizeof(ll) && 843 ll.ll_time != 0) { 844 (void)printf("Last login: %.*s ", 845 24-5, (char *)ctime(&ll.ll_time)); 846 if (*ll.ll_host != '\0') 847 (void)printf("from %.*s\n", 848 (int)sizeof(ll.ll_host), 849 ll.ll_host); 850 else 851 (void)printf("on %.*s\n", 852 (int)sizeof(ll.ll_line), 853 ll.ll_line); 854 } 855 (void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), L_SET); 856 } 857 memset((void *)&ll, 0, sizeof(ll)); 858 (void)time(&ll.ll_time); 859 (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line)); 860 if (hostname) 861 (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host)); 862 (void)write(fd, (char *)&ll, sizeof(ll)); 863 (void)close(fd); 864 } 865 } 866 867 void 868 badlogin(name) 869 char *name; 870 { 871 872 if (failures == 0) 873 return; 874 if (hostname) { 875 syslog(LOG_NOTICE, "%d LOGIN FAILURE%s FROM %s", 876 failures, failures > 1 ? "S" : "", full_hostname); 877 syslog(LOG_AUTHPRIV|LOG_NOTICE, 878 "%d LOGIN FAILURE%s FROM %s, %s", 879 failures, failures > 1 ? "S" : "", full_hostname, name); 880 } else { 881 syslog(LOG_NOTICE, "%d LOGIN FAILURE%s ON %s", 882 failures, failures > 1 ? "S" : "", tty); 883 syslog(LOG_AUTHPRIV|LOG_NOTICE, 884 "%d LOGIN FAILURE%s ON %s, %s", 885 failures, failures > 1 ? "S" : "", tty, name); 886 } 887 failures = 0; 888 } 889 890 #undef UNKNOWN 891 #define UNKNOWN "su" 892 893 char * 894 stypeof(ttyid) 895 char *ttyid; 896 { 897 898 struct ttyent *t; 899 900 return (ttyid && (t = getttynam(ttyid)) ? t->ty_type : UNKNOWN); 901 } 902 903 void 904 refused(msg, rtype, lout) 905 char *msg; 906 char *rtype; 907 int lout; 908 { 909 910 if (msg != NULL) 911 printf("%s.\n", msg); 912 if (hostname) 913 syslog(LOG_NOTICE, "LOGIN %s REFUSED (%s) FROM %s ON TTY %s", 914 pwd->pw_name, rtype, full_hostname, tty); 915 else 916 syslog(LOG_NOTICE, "LOGIN %s REFUSED (%s) ON TTY %s", 917 pwd->pw_name, rtype, tty); 918 if (lout) 919 sleepexit(1); 920 } 921 922 void 923 sleepexit(eval) 924 int eval; 925 { 926 927 (void)sleep(5); 928 exit(eval); 929 } 930