1/* $OpenBSD: login.c,v 1.74 2023/03/08 04:43:11 guenther Exp $ */ 2/* $NetBSD: login.c,v 1.13 1996/05/15 23:50:16 jtc Exp $ */ 3 4/*- 5 * Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32/*- 33 * Copyright (c) 1995 Berkeley Software Design, Inc. All rights reserved. 34 * 35 * Redistribution and use in source and binary forms, with or without 36 * modification, are permitted provided that the following conditions 37 * are met: 38 * 1. Redistributions of source code must retain the above copyright 39 * notice, this list of conditions and the following disclaimer. 40 * 2. Redistributions in binary form must reproduce the above copyright 41 * notice, this list of conditions and the following disclaimer in the 42 * documentation and/or other materials provided with the distribution. 43 * 3. All advertising materials mentioning features or use of this software 44 * must display the following acknowledgement: 45 * This product includes software developed by Berkeley Software Design, 46 * Inc. 47 * 4. The name of Berkeley Software Design, Inc. may not be used to endorse 48 * or promote products derived from this software without specific prior 49 * written permission. 50 * 51 * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN, INC. ``AS IS'' AND 52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 54 * ARE DISCLAIMED. IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN, INC. BE LIABLE 55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 61 * SUCH DAMAGE. 62 * 63 * BSDI $From: login.c,v 2.28 1999/09/08 22:35:36 prb Exp $ 64 */ 65 66/* 67 * login [ name ] 68 * login -h hostname (for telnetd, etc.) 69 * login -f name (for pre-authenticated login: datakit, xterm, etc.) 70 * login -p (preserve existing environment; for getty) 71 */ 72 73#include <sys/socket.h> 74#include <sys/stat.h> 75#include <sys/time.h> 76#include <sys/resource.h> 77#include <sys/wait.h> 78 79#include <err.h> 80#include <errno.h> 81#include <fcntl.h> 82#include <grp.h> 83#include <login_cap.h> 84#include <netdb.h> 85#include <pwd.h> 86#include <signal.h> 87#include <stdarg.h> 88#include <stdio.h> 89#include <stdlib.h> 90#include <string.h> 91#include <syslog.h> 92#include <ttyent.h> 93#include <unistd.h> 94#include <limits.h> 95#include <utmp.h> 96#include <util.h> 97#include <bsd_auth.h> 98 99#include "pathnames.h" 100 101void badlogin(char *); 102void dolastlog(int); 103void getloginname(void); 104void motd(void); 105void quickexit(int); 106int rootterm(char *); 107void sigint(int); 108void sighup(int); 109void sleepexit(int); 110char *stypeof(char *); 111void timedout(int); 112int main(int, char **); 113 114extern int check_failedlogin(uid_t); 115extern void log_failedlogin(uid_t, char *, char *, char *); 116 117#define TTYGRPNAME "tty" /* name of group to own ttys */ 118 119#define SECSPERDAY (24 * 60 * 60) 120#define TWOWEEKS (2 * 7 * SECSPERDAY) 121 122/* 123 * This bounds the time given to login; may be overridden by /etc/login.conf. 124 */ 125u_int timeout = 300; 126 127struct passwd *pwd; 128login_cap_t *lc = NULL; 129auth_session_t *as = NULL; 130int failures; 131int needbanner = 1; 132char term[64], *hostname, *tty; 133char *style; 134char *username = NULL, *rusername = NULL; 135 136extern char **environ; 137 138int 139main(int argc, char *argv[]) 140{ 141 char *domain, *p, *ttyn, *shell, *fullname, *instance; 142 char *lipaddr, *script, *ripaddr, *style, *type, *fqdn; 143 char tbuf[PATH_MAX + 2], tname[sizeof(_PATH_TTY) + 10]; 144 char localhost[HOST_NAME_MAX+1], *copyright; 145 char mail[sizeof(_PATH_MAILDIR) + 1 + NAME_MAX]; 146 int ask, ch, cnt, fflag, pflag, quietlog, rootlogin, lastchance; 147 int error, homeless, needto, authok, tries, backoff; 148 struct addrinfo *ai, hints; 149 struct rlimit cds, scds; 150 quad_t expire, warning; 151 struct utmp utmp; 152 struct group *gr; 153 struct stat st; 154 uid_t uid; 155 156 openlog("login", LOG_ODELAY, LOG_AUTH); 157 158 fqdn = lipaddr = ripaddr = fullname = type = NULL; 159 authok = 0; 160 tries = 10; 161 backoff = 3; 162 163 domain = NULL; 164 if (gethostname(localhost, sizeof(localhost)) == -1) { 165 syslog(LOG_ERR, "couldn't get local hostname: %m"); 166 strlcpy(localhost, "localhost", sizeof(localhost)); 167 } else if ((domain = strchr(localhost, '.'))) { 168 domain++; 169 if (*domain && strchr(domain, '.') == NULL) 170 domain = localhost; 171 } 172 173 if ((as = auth_open()) == NULL) { 174 syslog(LOG_ERR, "auth_open: %m"); 175 err(1, "unable to initialize BSD authentication"); 176 } 177 auth_setoption(as, "login", "yes"); 178 179 /* 180 * -p is used by getty to tell login not to destroy the environment 181 * -f is used to skip a second login authentication 182 * -h is used by other servers to pass the name of the remote 183 * host to login so that it may be placed in utmp and wtmp 184 */ 185 fflag = pflag = 0; 186 uid = getuid(); 187 while ((ch = getopt(argc, argv, "fh:pu:L:R:")) != -1) 188 switch (ch) { 189 case 'f': 190 fflag = 1; 191 break; 192 case 'h': 193 if (uid) { 194 warnc(EPERM, "-h option"); 195 quickexit(1); 196 } 197 free(fqdn); 198 if ((fqdn = strdup(optarg)) == NULL) { 199 warn(NULL); 200 quickexit(1); 201 } 202 auth_setoption(as, "fqdn", fqdn); 203 if (domain && (p = strchr(optarg, '.')) && 204 strcasecmp(p+1, domain) == 0) 205 *p = 0; 206 hostname = optarg; 207 auth_setoption(as, "hostname", hostname); 208 break; 209 case 'L': 210 if (uid) { 211 warnc(EPERM, "-L option"); 212 quickexit(1); 213 } 214 if (lipaddr) { 215 warnx("duplicate -L option"); 216 quickexit(1); 217 } 218 lipaddr = optarg; 219 memset(&hints, 0, sizeof(hints)); 220 hints.ai_family = PF_UNSPEC; 221 hints.ai_flags = AI_CANONNAME; 222 error = getaddrinfo(lipaddr, NULL, &hints, &ai); 223 if (!error) { 224 strlcpy(localhost, ai->ai_canonname, 225 sizeof(localhost)); 226 freeaddrinfo(ai); 227 } else 228 strlcpy(localhost, lipaddr, sizeof(localhost)); 229 auth_setoption(as, "local_addr", lipaddr); 230 break; 231 case 'p': 232 pflag = 1; 233 break; 234 case 'R': 235 if (uid) { 236 warnc(EPERM, "-R option"); 237 quickexit(1); 238 } 239 if (ripaddr) { 240 warnx("duplicate -R option"); 241 quickexit(1); 242 } 243 ripaddr = optarg; 244 auth_setoption(as, "remote_addr", ripaddr); 245 break; 246 case 'u': 247 if (uid) { 248 warnc(EPERM, "-u option"); 249 quickexit(1); 250 } 251 rusername = optarg; 252 break; 253 default: 254 if (!uid) 255 syslog(LOG_ERR, "invalid flag %c", ch); 256 (void)fprintf(stderr, 257 "usage: login [-fp] [-h hostname] [-L local-addr] " 258 "[-R remote-addr] [-u username]\n\t[user]\n"); 259 quickexit(1); 260 } 261 argc -= optind; 262 argv += optind; 263 264 if (*argv) { 265 username = *argv; 266 ask = 0; 267 } else 268 ask = 1; 269 270 /* 271 * If effective user is not root, just run su(1) to emulate login(1). 272 */ 273 if (geteuid() != 0) { 274 char *av[5], **ap; 275 276 auth_close(as); 277 closelog(); 278 closefrom(STDERR_FILENO + 1); 279 280 ap = av; 281 *ap++ = _PATH_SU; 282 *ap++ = "-L"; 283 if (!pflag) 284 *ap++ = "-l"; 285 if (!ask) 286 *ap++ = username; 287 *ap = NULL; 288 execv(_PATH_SU, av); 289 warn("unable to exec %s", _PATH_SU); 290 _exit(1); 291 } 292 293 ttyn = ttyname(STDIN_FILENO); 294 if (ttyn == NULL || *ttyn == '\0') { 295 (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY); 296 ttyn = tname; 297 } 298 if ((tty = strrchr(ttyn, '/'))) 299 ++tty; 300 else 301 tty = ttyn; 302 303 /* 304 * Since login deals with sensitive information, turn off coredumps. 305 */ 306 if (getrlimit(RLIMIT_CORE, &scds) == -1) { 307 syslog(LOG_ERR, "couldn't get core dump size: %m"); 308 scds.rlim_cur = scds.rlim_max = QUAD_MIN; 309 } 310 cds.rlim_cur = cds.rlim_max = 0; 311 if (setrlimit(RLIMIT_CORE, &cds) == -1) { 312 syslog(LOG_ERR, "couldn't set core dump size to 0: %m"); 313 scds.rlim_cur = scds.rlim_max = QUAD_MIN; 314 } 315 316 (void)signal(SIGALRM, timedout); 317 if (argc > 1) { 318 needto = 0; 319 (void)alarm(timeout); 320 } else 321 needto = 1; 322 (void)signal(SIGQUIT, SIG_IGN); 323 (void)signal(SIGINT, SIG_IGN); 324 (void)signal(SIGHUP, SIG_IGN); 325 (void)setpriority(PRIO_PROCESS, 0, 0); 326 327 /* get the default login class */ 328 if ((lc = login_getclass(0)) == NULL) { /* get the default class */ 329 warnx("Failure to retrieve default class"); 330 quickexit(1); 331 } 332 timeout = (u_int)login_getcapnum(lc, "login-timeout", 300, 300); 333 if ((script = login_getcapstr(lc, "classify", NULL, NULL)) != NULL) { 334 unsetenv("AUTH_TYPE"); 335 unsetenv("REMOTE_NAME"); 336 if (script[0] != '/') { 337 syslog(LOG_ERR, "Invalid classify script: %s", script); 338 warnx("Classification failure"); 339 quickexit(1); 340 } 341 shell = strrchr(script, '/') + 1; 342 auth_setstate(as, AUTH_OKAY); 343 if (fflag) { 344 auth_call(as, script, shell, "-f", "--", username, 345 (char *)NULL); 346 } else { 347 auth_call(as, script, shell, "--", username, 348 (char *)NULL); 349 } 350 if (!(auth_getstate(as) & AUTH_ALLOW)) 351 quickexit(1); 352 auth_setenv(as); 353 if ((p = getenv("AUTH_TYPE")) != NULL && 354 strncmp(p, "auth-", 5) == 0) 355 type = p; 356 if ((p = getenv("REMOTE_NAME")) != NULL) 357 hostname = p; 358 /* 359 * we may have changed some values, reset them 360 */ 361 auth_clroptions(as); 362 if (type) 363 auth_setoption(as, "auth_type", type); 364 if (fqdn) 365 auth_setoption(as, "fqdn", fqdn); 366 if (hostname) 367 auth_setoption(as, "hostname", hostname); 368 if (lipaddr) 369 auth_setoption(as, "local_addr", lipaddr); 370 if (ripaddr) 371 auth_setoption(as, "remote_addr", ripaddr); 372 } 373 374 /* 375 * Request that things like the approval script print things 376 * to stdout (in particular, the nologins files) 377 */ 378 auth_setitem(as, AUTHV_INTERACTIVE, "True"); 379 380 for (cnt = 0;; ask = 1) { 381 /* 382 * Clean up our current authentication session. 383 * Options are not cleared so we need to clear any 384 * we might set below. 385 */ 386 auth_clean(as); 387 auth_clroption(as, "style"); 388 auth_clroption(as, "lastchance"); 389 390 lastchance = 0; 391 392 if (ask) { 393 fflag = 0; 394 getloginname(); 395 } 396 if (needto) { 397 needto = 0; 398 alarm(timeout); 399 } 400 if ((style = strchr(username, ':')) != NULL) 401 *style++ = '\0'; 402 free(fullname); 403 if (auth_setitem(as, AUTHV_NAME, username) < 0 || 404 (fullname = strdup(username)) == NULL) { 405 syslog(LOG_ERR, "%m"); 406 warn(NULL); 407 quickexit(1); 408 } 409 rootlogin = 0; 410 if ((instance = strchr(username, '/')) != NULL) { 411 if (strncmp(instance + 1, "root", 4) == 0) 412 rootlogin = 1; 413 *instance = '\0'; 414 } 415 416 if (strlen(username) > UT_NAMESIZE) 417 username[UT_NAMESIZE] = '\0'; 418 419 /* 420 * Note if trying multiple user names; log failures for 421 * previous user name, but don't bother logging one failure 422 * for nonexistent name (mistyped username). 423 */ 424 if (failures && strcmp(tbuf, username)) { 425 if (failures > (pwd ? 0 : 1)) 426 badlogin(tbuf); 427 failures = 0; 428 } 429 (void)strlcpy(tbuf, username, sizeof(tbuf)); 430 431 if ((pwd = getpwnam(username)) != NULL && 432 auth_setpwd(as, pwd) < 0) { 433 syslog(LOG_ERR, "%m"); 434 warn(NULL); 435 quickexit(1); 436 } 437 438 lc = login_getclass(pwd ? pwd->pw_class : NULL); 439 if (!lc) 440 goto failed; 441 442 style = login_getstyle(lc, style, type); 443 if (!style) 444 goto failed; 445 446 /* 447 * We allow "login-tries" attempts to login but start 448 * slowing down after "login-backoff" attempts. 449 */ 450 tries = (int)login_getcapnum(lc, "login-tries", 10, 10); 451 backoff = (int)login_getcapnum(lc, "login-backoff", 3, 3); 452 453 /* 454 * Turn off the fflag if we have an invalid user 455 * or we are not root and we are trying to change uids. 456 */ 457 if (!pwd || (uid && uid != pwd->pw_uid)) 458 fflag = 0; 459 460 if (pwd && pwd->pw_uid == 0) 461 rootlogin = 1; 462 463 /* 464 * If we do not have the force flag authenticate the user 465 */ 466 if (!fflag) { 467 lastchance = 468 login_getcaptime(lc, "password-dead", 0, 0) != 0; 469 if (lastchance) 470 auth_setoption(as, "lastchance", "yes"); 471 /* 472 * Once we start asking for a password 473 * we want to log a failure on a hup. 474 */ 475 signal(SIGHUP, sighup); 476 auth_verify(as, style, NULL, lc->lc_class, NULL); 477 authok = auth_getstate(as); 478 /* 479 * If their password expired and it has not been 480 * too long since then, give the user one last 481 * chance to change their password 482 */ 483 if ((authok & AUTH_PWEXPIRED) && lastchance) { 484 authok = AUTH_OKAY; 485 } else 486 lastchance = 0; 487 if ((authok & AUTH_ALLOW) == 0) 488 goto failed; 489 if (auth_setoption(as, "style", style) < 0) { 490 syslog(LOG_ERR, "%m"); 491 warn(NULL); 492 quickexit(1); 493 } 494 } 495 /* 496 * explicitly reject users without password file entries 497 */ 498 if (pwd == NULL) 499 goto failed; 500 501 /* 502 * If trying to log in as root on an insecure terminal, 503 * refuse the login attempt unless the authentication 504 * style explicitly says a root login is okay. 505 */ 506 if (pwd && rootlogin && !rootterm(tty)) 507 goto failed; 508 509 if (fflag) { 510 type = 0; 511 style = "forced"; 512 } 513 break; 514 515failed: 516 if (authok & AUTH_SILENT) 517 quickexit(0); 518 if (rootlogin && !rootterm(tty)) { 519 warnx("%s login refused on this terminal.", 520 fullname); 521 if (hostname) 522 syslog(LOG_NOTICE, 523 "LOGIN %s REFUSED FROM %s%s%s ON TTY %s", 524 fullname, rusername ? rusername : "", 525 rusername ? "@" : "", hostname, tty); 526 else 527 syslog(LOG_NOTICE, 528 "LOGIN %s REFUSED ON TTY %s", 529 fullname, tty); 530 } else { 531 if (!as || (p = auth_getvalue(as, "errormsg")) == NULL) 532 p = "Login incorrect"; 533 (void)printf("%s\n", p); 534 } 535 failures++; 536 if (pwd) 537 log_failedlogin(pwd->pw_uid, hostname, rusername, tty); 538 /* 539 * By default, we allow 10 tries, but after 3 we start 540 * backing off to slow down password guessers. 541 */ 542 if (++cnt > backoff) { 543 if (cnt >= tries) { 544 badlogin(username); 545 sleepexit(1); 546 } 547 sleep(1); 548 } 549 } 550 551 /* committed to login -- turn off timeout */ 552 (void)alarm(0); 553 554 endpwent(); 555 556 shell = login_getcapstr(lc, "shell", pwd->pw_shell, pwd->pw_shell); 557 if (*shell == '\0') 558 shell = _PATH_BSHELL; 559 else if (strlen(shell) >= PATH_MAX) { 560 syslog(LOG_ERR, "shell path too long: %s", shell); 561 warnx("invalid shell"); 562 quickexit(1); 563 } 564 565 /* Destroy environment unless user has requested its preservation. */ 566 if (!pflag) { 567 if ((environ = calloc(1, sizeof (char *))) == NULL) 568 err(1, "calloc"); 569 } else { 570 char **cpp, **cpp2; 571 572 for (cpp2 = cpp = environ; *cpp; cpp++) { 573 if (strncmp(*cpp, "LD_", 3) && 574 strncmp(*cpp, "ENV=", 4) && 575 strncmp(*cpp, "BASH_ENV=", 9) && 576 strncmp(*cpp, "IFS=", 4)) 577 *cpp2++ = *cpp; 578 } 579 *cpp2 = 0; 580 } 581 /* Note: setusercontext(3) will set PATH */ 582 if (setenv("HOME", pwd->pw_dir, 1) == -1 || 583 setenv("SHELL", pwd->pw_shell, 1) == -1) { 584 warn("unable to setenv()"); 585 quickexit(1); 586 } 587 if (term[0] == '\0') 588 (void)strlcpy(term, stypeof(tty), sizeof(term)); 589 (void)snprintf(mail, sizeof(mail), "%s/%s", _PATH_MAILDIR, 590 pwd->pw_name); 591 if (setenv("TERM", term, 0) == -1 || 592 setenv("LOGNAME", pwd->pw_name, 1) == -1 || 593 setenv("USER", pwd->pw_name, 1) == -1 || 594 setenv("MAIL", mail, 1) == -1) { 595 warn("unable to setenv()"); 596 quickexit(1); 597 } 598 if (hostname) { 599 if (setenv("REMOTEHOST", hostname, 1) == -1) { 600 warn("unable to setenv()"); 601 quickexit(1); 602 } 603 } 604 if (rusername) { 605 if (setenv("REMOTEUSER", rusername, 1) == -1) { 606 warn("unable to setenv()"); 607 quickexit(1); 608 } 609 } 610 611 if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETPATH)) { 612 warn("unable to set user context"); 613 quickexit(1); 614 } 615 auth_setenv(as); 616 617 /* if user not super-user, check for disabled logins */ 618 if (!rootlogin) 619 auth_checknologin(lc); 620 621 setegid(pwd->pw_gid); 622 seteuid(pwd->pw_uid); 623 624 homeless = chdir(pwd->pw_dir); 625 if (homeless) { 626 if (login_getcapbool(lc, "requirehome", 0)) { 627 (void)printf("No home directory %s!\n", pwd->pw_dir); 628 quickexit(1); 629 } 630 if (chdir("/")) 631 quickexit(0); 632 } 633 634 quietlog = ((strcmp(pwd->pw_shell, "/sbin/nologin") == 0) || 635 login_getcapbool(lc, "hushlogin", 0) || 636 (access(_PATH_HUSHLOGIN, F_OK) == 0)); 637 638 seteuid(0); 639 setegid(0); /* XXX use a saved gid instead? */ 640 641 if ((p = auth_getvalue(as, "warnmsg")) != NULL) 642 (void)printf("WARNING: %s\n\n", p); 643 644 expire = auth_check_expire(as); 645 if (expire < 0) { 646 (void)printf("Sorry -- your account has expired.\n"); 647 quickexit(1); 648 } else if (expire > 0 && !quietlog) { 649 warning = login_getcaptime(lc, "expire-warn", 650 TWOWEEKS, TWOWEEKS); 651 if (expire < warning) 652 (void)printf("Warning: your account expires on %s", 653 ctime(&pwd->pw_expire)); 654 } 655 656 /* Nothing else left to fail -- really log in. */ 657 (void)signal(SIGHUP, SIG_DFL); 658 memset(&utmp, 0, sizeof(utmp)); 659 (void)time(&utmp.ut_time); 660 (void)strncpy(utmp.ut_name, username, sizeof(utmp.ut_name)); 661 if (hostname) 662 (void)strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host)); 663 (void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line)); 664 login(&utmp); 665 666 if (!quietlog) 667 (void)check_failedlogin(pwd->pw_uid); 668 dolastlog(quietlog); 669 670 login_fbtab(tty, pwd->pw_uid, pwd->pw_gid); 671 672 (void)chown(ttyn, pwd->pw_uid, 673 (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid); 674 675 /* If fflag is on, assume caller/authenticator has logged root login. */ 676 if (rootlogin && fflag == 0) { 677 if (hostname) 678 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s%s%s", 679 username, tty, rusername ? rusername : "", 680 rusername ? "@" : "", hostname); 681 else 682 syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s", username, tty); 683 } 684 685 if (!quietlog) { 686 if ((copyright = 687 login_getcapstr(lc, "copyright", NULL, NULL)) != NULL) 688 auth_cat(copyright); 689 motd(); 690 if (stat(mail, &st) == 0 && st.st_size != 0) 691 (void)printf("You have %smail.\n", 692 (st.st_mtime > st.st_atime) ? "new " : ""); 693 } 694 695 (void)signal(SIGALRM, SIG_DFL); 696 (void)signal(SIGQUIT, SIG_DFL); 697 (void)signal(SIGHUP, SIG_DFL); 698 (void)signal(SIGINT, SIG_DFL); 699 (void)signal(SIGTSTP, SIG_IGN); 700 701 tbuf[0] = '-'; 702 (void)strlcpy(tbuf + 1, (p = strrchr(shell, '/')) ? 703 p + 1 : shell, sizeof(tbuf) - 1); 704 705 if ((scds.rlim_cur != QUAD_MIN || scds.rlim_max != QUAD_MIN) && 706 setrlimit(RLIMIT_CORE, &scds) == -1) 707 syslog(LOG_ERR, "couldn't reset core dump size: %m"); 708 709 if (lastchance) 710 (void)printf("WARNING: Your password has expired." 711 " You must change your password, now!\n"); 712 713 if (setusercontext(lc, pwd, rootlogin ? 0 : pwd->pw_uid, 714 LOGIN_SETALL & ~LOGIN_SETPATH) < 0) { 715 warn("unable to set user context"); 716 quickexit(1); 717 } 718 719 if (homeless) { 720 (void)printf("No home directory %s!\n", pwd->pw_dir); 721 (void)printf("Logging in with home = \"/\".\n"); 722 (void)setenv("HOME", "/", 1); 723 } 724 725 if (auth_approval(as, lc, NULL, "login") == 0) { 726 if (auth_getstate(as) & AUTH_EXPIRED) 727 (void)printf("Sorry -- your account has expired.\n"); 728 else 729 (void)printf("approval failure\n"); 730 quickexit(1); 731 } 732 733 /* 734 * The last thing we do is discard all of the open file descriptors. 735 * Last because the C library may have some open. 736 */ 737 closefrom(STDERR_FILENO + 1); 738 739 /* 740 * Close the authentication session, make sure it is marked 741 * as okay so no files are removed. 742 */ 743 auth_setstate(as, AUTH_OKAY); 744 auth_close(as); 745 746 execlp(shell, tbuf, (char *)NULL); 747 err(1, "%s", shell); 748} 749 750/* 751 * Allow for a '.' and 16 characters for any instance as well as 752 * space for a ':' and 16 characters defining the authentication type. 753 */ 754#define NBUFSIZ (UT_NAMESIZE + 1 + 16 + 1 + 16) 755 756void 757getloginname(void) 758{ 759 static char nbuf[NBUFSIZ], *p; 760 int ch; 761 762 for (;;) { 763 (void)printf("login: "); 764 for (p = nbuf; (ch = getchar()) != '\n'; ) { 765 if (ch == EOF) { 766 badlogin(username); 767 quickexit(0); 768 } 769 if (p < nbuf + (NBUFSIZ - 1)) 770 *p++ = ch; 771 } 772 if (p > nbuf) { 773 if (nbuf[0] == '-') 774 (void)fprintf(stderr, 775 "login names may not start with '-'.\n"); 776 else { 777 *p = '\0'; 778 username = nbuf; 779 break; 780 } 781 } 782 } 783} 784 785int 786rootterm(char *ttyn) 787{ 788 struct ttyent *t; 789 790 /* XXX - stash output of getttynam() elsewhere */ 791 return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE); 792} 793 794void 795motd(void) 796{ 797 char tbuf[8192], *motd; 798 int fd, nchars; 799 struct sigaction sa, osa; 800 801 motd = login_getcapstr(lc, "welcome", _PATH_MOTDFILE, _PATH_MOTDFILE); 802 803 if ((fd = open(motd, O_RDONLY)) == -1) 804 return; 805 806 memset(&sa, 0, sizeof(sa)); 807 sa.sa_handler = sigint; 808 sigemptyset(&sa.sa_mask); 809 sa.sa_flags = 0; /* don't set SA_RESTART */ 810 (void)sigaction(SIGINT, &sa, &osa); 811 812 /* read and spew motd until EOF, error, or SIGINT */ 813 while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0 && 814 write(STDOUT_FILENO, tbuf, nchars) == nchars) 815 ; 816 817 (void)sigaction(SIGINT, &osa, NULL); 818 (void)close(fd); 819} 820 821void 822sigint(int signo) 823{ 824 return; /* just interrupt syscall */ 825} 826 827void 828timedout(int signo) 829{ 830 dprintf(STDERR_FILENO, 831 "Login timed out after %d seconds\n", timeout); 832 if (username) 833 badlogin(username); 834 _exit(0); 835} 836 837void 838dolastlog(int quiet) 839{ 840 struct lastlog ll; 841 off_t pos; 842 int fd; 843 844 if ((fd = open(_PATH_LASTLOG, O_RDWR)) >= 0) { 845 pos = (off_t)pwd->pw_uid * sizeof(ll); 846 if (!quiet) { 847 if (pread(fd, &ll, sizeof(ll), pos) == sizeof(ll) && 848 ll.ll_time != 0) { 849 (void)printf("Last login: %.*s ", 850 24-5, (char *)ctime(&ll.ll_time)); 851 (void)printf("on %.*s", 852 (int)sizeof(ll.ll_line), 853 ll.ll_line); 854 if (*ll.ll_host != '\0') 855 (void)printf(" from %.*s", 856 (int)sizeof(ll.ll_host), 857 ll.ll_host); 858 (void)putchar('\n'); 859 } 860 } 861 memset(&ll, 0, sizeof(ll)); 862 (void)time(&ll.ll_time); 863 (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line)); 864 if (hostname) 865 (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host)); 866 (void)pwrite(fd, &ll, sizeof(ll), pos); 867 (void)close(fd); 868 } 869} 870 871void 872badlogin(char *name) 873{ 874 struct syslog_data sdata = SYSLOG_DATA_INIT; 875 876 if (failures == 0) 877 return; 878 if (hostname) { 879 syslog_r(LOG_NOTICE, &sdata, 880 "%d LOGIN FAILURE%s FROM %s%s%s", 881 failures, failures > 1 ? "S" : "", 882 rusername ? rusername : "", rusername ? "@" : "", hostname); 883 syslog_r(LOG_AUTHPRIV|LOG_NOTICE, &sdata, 884 "%d LOGIN FAILURE%s FROM %s%s%s, %s", 885 failures, failures > 1 ? "S" : "", 886 rusername ? rusername : "", rusername ? "@" : "", 887 hostname, name); 888 } else { 889 syslog_r(LOG_NOTICE, &sdata, 890 "%d LOGIN FAILURE%s ON %s", 891 failures, failures > 1 ? "S" : "", tty); 892 syslog_r(LOG_AUTHPRIV|LOG_NOTICE, &sdata, 893 "%d LOGIN FAILURE%s ON %s, %s", 894 failures, failures > 1 ? "S" : "", tty, name); 895 } 896} 897 898#undef UNKNOWN 899#define UNKNOWN "su" 900 901char * 902stypeof(char *ttyid) 903{ 904 struct ttyent *t; 905 906 return (ttyid && (t = getttynam(ttyid)) ? t->ty_type : 907 login_getcapstr(lc, "term", UNKNOWN, UNKNOWN)); 908} 909 910void 911sleepexit(int eval) 912{ 913 auth_close(as); 914 (void)sleep(5); 915 exit(eval); 916} 917 918void 919quickexit(int eval) 920{ 921 if (as) 922 auth_close(as); 923 exit(eval); 924} 925 926 927void 928sighup(int signum) 929{ 930 if (username) 931 badlogin(username); 932 _exit(0); 933} 934