Annotation of src/usr.bin/login/login.c, Revision 1.58
1.58 ! martynas 1: /* $OpenBSD: login.c,v 1.57 2007/04/02 07:01:33 jmc Exp $ */
1.3 deraadt 2: /* $NetBSD: login.c,v 1.13 1996/05/15 23:50:16 jtc Exp $ */
1.1 deraadt 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.
1.50 millert 16: * 3. Neither the name of the University nor the names of its contributors
1.1 deraadt 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: */
1.36 millert 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: */
1.1 deraadt 65:
66: #ifndef lint
1.49 millert 67: static const char copyright[] =
1.1 deraadt 68: "@(#) Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994\n\
69: The Regents of the University of California. All rights reserved.\n";
70: #endif /* not lint */
71:
72: #ifndef lint
73: #if 0
1.49 millert 74: static const char sccsid[] = "@(#)login.c 8.4 (Berkeley) 4/2/94";
1.1 deraadt 75: #endif
1.58 ! martynas 76: static const char rcsid[] = "$OpenBSD: login.c,v 1.57 2007/04/02 07:01:33 jmc Exp $";
1.1 deraadt 77: #endif /* not lint */
78:
79: /*
80: * login [ name ]
81: * login -h hostname (for telnetd, etc.)
82: * login -f name (for pre-authenticated login: datakit, xterm, etc.)
1.49 millert 83: * login -p (preserve existing environment; for getty)
1.1 deraadt 84: */
85:
86: #include <sys/param.h>
1.36 millert 87: #include <sys/socket.h>
1.1 deraadt 88: #include <sys/stat.h>
89: #include <sys/time.h>
90: #include <sys/resource.h>
1.11 millert 91: #include <sys/wait.h>
1.1 deraadt 92:
93: #include <err.h>
94: #include <errno.h>
1.27 millert 95: #include <fcntl.h>
1.1 deraadt 96: #include <grp.h>
1.30 millert 97: #include <login_cap.h>
1.36 millert 98: #include <netdb.h>
1.1 deraadt 99: #include <pwd.h>
100: #include <signal.h>
1.36 millert 101: #include <stdarg.h>
1.1 deraadt 102: #include <stdio.h>
103: #include <stdlib.h>
104: #include <string.h>
105: #include <syslog.h>
106: #include <ttyent.h>
107: #include <tzfile.h>
108: #include <unistd.h>
109: #include <utmp.h>
1.3 deraadt 110: #include <util.h>
1.36 millert 111: #include <bsd_auth.h>
112:
1.1 deraadt 113: #include "pathnames.h"
114:
1.45 millert 115: void badlogin(char *);
116: void dolastlog(int);
117: void getloginname(void);
118: void motd(void);
119: void quickexit(int);
120: int rootterm(char *);
121: void sigint(int);
122: void sighup(int);
123: void sleepexit(int);
124: char *stypeof(char *);
125: void timedout(int);
126: int main(int, char **);
1.1 deraadt 127:
1.45 millert 128: extern int check_failedlogin(uid_t);
129: extern void log_failedlogin(uid_t, char *, char *, char *);
1.1 deraadt 130:
131: #define TTYGRPNAME "tty" /* name of group to own ttys */
132:
133: /*
1.37 millert 134: * This bounds the time given to login; may be overridden by /etc/login.conf.
1.1 deraadt 135: */
1.30 millert 136: u_int timeout = 300;
1.1 deraadt 137:
1.36 millert 138: struct passwd *pwd;
1.30 millert 139: login_cap_t *lc = NULL;
1.36 millert 140: auth_session_t *as = NULL;
1.30 millert 141: int failures;
1.36 millert 142: int needbanner = 1;
1.30 millert 143: char term[64], *hostname, *tty;
1.36 millert 144: char *style;
1.30 millert 145: char *username = NULL, *rusername = NULL;
1.1 deraadt 146:
1.47 deraadt 147: extern char **environ;
148:
1.1 deraadt 149: int
1.47 deraadt 150: main(int argc, char *argv[])
1.1 deraadt 151: {
1.47 deraadt 152: char *domain, *p, *ttyn, *shell, *fullname, *instance;
153: char *lipaddr, *script, *ripaddr, *style, *type, *fqdn;
154: char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10];
155: char localhost[MAXHOSTNAMELEN], *copyright;
156: int ask, ch, cnt, fflag, pflag, quietlog, rootlogin, lastchance;
157: int error, homeless, needto, authok, tries, backoff;
1.36 millert 158: struct addrinfo *ai, hints;
1.47 deraadt 159: struct rlimit cds, scds;
160: quad_t expire, warning;
161: struct utmp utmp;
1.1 deraadt 162: struct group *gr;
163: struct stat st;
164: uid_t uid;
165:
166: openlog("login", LOG_ODELAY, LOG_AUTH);
167:
1.37 millert 168: fqdn = lipaddr = ripaddr = fullname = type = NULL;
169: authok = 0;
170: tries = 10;
171: backoff = 3;
1.36 millert 172:
1.1 deraadt 173: domain = NULL;
1.49 millert 174: if (gethostname(localhost, sizeof(localhost)) < 0) {
1.1 deraadt 175: syslog(LOG_ERR, "couldn't get local hostname: %m");
1.49 millert 176: strlcpy(localhost, "localhost", sizeof(localhost));
177: } else if ((domain = strchr(localhost, '.'))) {
1.21 deraadt 178: domain++;
179: if (*domain && strchr(domain, '.') == NULL)
180: domain = localhost;
181: }
1.1 deraadt 182:
1.36 millert 183: if ((as = auth_open()) == NULL) {
1.39 millert 184: syslog(LOG_ERR, "auth_open: %m");
185: err(1, "unable to initialize BSD authentication");
1.36 millert 186: }
1.39 millert 187: auth_setoption(as, "login", "yes");
1.36 millert 188:
1.49 millert 189: /*
190: * -p is used by getty to tell login not to destroy the environment
191: * -f is used to skip a second login authentication
192: * -h is used by other servers to pass the name of the remote
193: * host to login so that it may be placed in utmp and wtmp
194: */
1.36 millert 195: fflag = pflag = 0;
1.1 deraadt 196: uid = getuid();
1.36 millert 197: while ((ch = getopt(argc, argv, "fh:pu:L:R:")) != -1)
1.1 deraadt 198: switch (ch) {
199: case 'f':
200: fflag = 1;
201: break;
202: case 'h':
1.36 millert 203: if (uid) {
1.46 vincent 204: warnx("-h option: %s", strerror(EPERM));
1.36 millert 205: quickexit(1);
206: }
207: if ((fqdn = strdup(optarg)) == NULL) {
208: warn(NULL);
209: quickexit(1);
210: }
211: auth_setoption(as, "fqdn", fqdn);
1.1 deraadt 212: if (domain && (p = strchr(optarg, '.')) &&
1.21 deraadt 213: strcasecmp(p+1, domain) == 0)
1.1 deraadt 214: *p = 0;
215: hostname = optarg;
1.36 millert 216: auth_setoption(as, "hostname", hostname);
217: break;
218: case 'L':
219: if (uid) {
220: warnx("-L option: %s", strerror(EPERM));
221: quickexit(1);
222: }
223: if (lipaddr) {
224: warnx("duplicate -L option");
225: quickexit(1);
226: }
227: lipaddr = optarg;
228: memset(&hints, 0, sizeof(hints));
229: hints.ai_family = PF_UNSPEC;
230: hints.ai_flags = AI_CANONNAME;
231: error = getaddrinfo(lipaddr, NULL, &hints, &ai);
232: if (!error) {
233: strlcpy(localhost, ai->ai_canonname,
234: sizeof(localhost));
235: freeaddrinfo(ai);
236: } else
237: strlcpy(localhost, lipaddr, sizeof(localhost));
238: auth_setoption(as, "local_addr", lipaddr);
1.1 deraadt 239: break;
240: case 'p':
241: pflag = 1;
242: break;
1.36 millert 243: case 'R':
244: if (uid) {
245: warnx("-R option: %s", strerror(EPERM));
246: quickexit(1);
247: }
248: if (ripaddr) {
249: warnx("duplicate -R option");
250: quickexit(1);
251: }
252: ripaddr = optarg;
253: auth_setoption(as, "remote_addr", ripaddr);
254: break;
1.14 millert 255: case 'u':
1.36 millert 256: if (uid) {
257: warnx("-u option: %s", strerror(EPERM));
258: quickexit(1);
259: }
1.14 millert 260: rusername = optarg;
261: break;
1.1 deraadt 262: default:
263: if (!uid)
264: syslog(LOG_ERR, "invalid flag %c", ch);
265: (void)fprintf(stderr,
1.57 jmc 266: "usage: login [-fp] [-h hostname] [-L local-addr] "
267: "[-R remote-addr] [-u username]\n\t[user]\n");
1.36 millert 268: quickexit(1);
1.1 deraadt 269: }
270: argc -= optind;
271: argv += optind;
272:
273: if (*argv) {
274: username = *argv;
275: ask = 0;
276: } else
277: ask = 1;
278:
1.49 millert 279: /*
280: * If effective user is not root, just run su(1) to emulate login(1).
281: */
282: if (geteuid() != 0) {
283: char *av[5], **ap;
284:
285: auth_close(as);
286: closelog();
1.54 millert 287: closefrom(STDERR_FILENO + 1);
1.49 millert 288:
289: ap = av;
290: *ap++ = _PATH_SU;
291: *ap++ = "-L";
292: if (!pflag)
293: *ap++ = "-l";
294: if (!ask)
295: *ap++ = username;
296: *ap = NULL;
297: execv(_PATH_SU, av);
298: warn("unable to exec %s", _PATH_SU);
299: _exit(1);
300: }
301:
1.1 deraadt 302: ttyn = ttyname(STDIN_FILENO);
303: if (ttyn == NULL || *ttyn == '\0') {
304: (void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY);
305: ttyn = tname;
306: }
1.12 millert 307: if ((tty = strrchr(ttyn, '/')))
1.1 deraadt 308: ++tty;
309: else
310: tty = ttyn;
311:
1.49 millert 312: /*
313: * Since login deals with sensitive information, turn off coredumps.
314: */
315: if (getrlimit(RLIMIT_CORE, &scds) < 0) {
316: syslog(LOG_ERR, "couldn't get core dump size: %m");
317: scds.rlim_cur = scds.rlim_max = QUAD_MIN;
318: }
319: cds.rlim_cur = cds.rlim_max = 0;
320: if (setrlimit(RLIMIT_CORE, &cds) < 0) {
321: syslog(LOG_ERR, "couldn't set core dump size to 0: %m");
322: scds.rlim_cur = scds.rlim_max = QUAD_MIN;
323: }
324:
325: (void)signal(SIGALRM, timedout);
326: if (argc > 1) {
327: needto = 0;
328: (void)alarm(timeout);
329: } else
330: needto = 1;
331: (void)signal(SIGQUIT, SIG_IGN);
332: (void)signal(SIGINT, SIG_IGN);
333: (void)signal(SIGHUP, SIG_IGN);
334: (void)setpriority(PRIO_PROCESS, 0, 0);
335:
1.36 millert 336: #ifdef notyet
337: /* XXX - we don't (yet) support per-tty auth stuff */
338: /* BSDi uses a ttys.conf file but we could just overload /etc/ttys */
339: /*
340: * Classify the attempt.
341: * By default we use the value in the ttys file.
342: * If there is a classify script we run that as
343: *
344: * classify [-f] [username]
345: */
346: if (type = getttyauth(tty))
347: auth_setoption(as, "auth_type", type);
348: #endif
349:
350: /* get the default login class */
1.47 deraadt 351: if ((lc = login_getclass(0)) == NULL) { /* get the default class */
1.36 millert 352: warnx("Failure to retrieve default class");
353: quickexit(1);
354: }
1.37 millert 355: timeout = (u_int)login_getcapnum(lc, "login-timeout", 300, 300);
1.36 millert 356: if ((script = login_getcapstr(lc, "classify", NULL, NULL)) != NULL) {
357: unsetenv("AUTH_TYPE");
358: unsetenv("REMOTE_NAME");
359: if (script[0] != '/') {
360: syslog(LOG_ERR, "Invalid classify script: %s", script);
361: warnx("Classification failure");
362: quickexit(1);
363: }
364: shell = strrchr(script, '/') + 1;
365: auth_setstate(as, AUTH_OKAY);
1.47 deraadt 366: auth_call(as, script, shell,
1.49 millert 367: fflag ? "-f" : username, fflag ? username : 0, (char *)0);
1.36 millert 368: if (!(auth_getstate(as) & AUTH_ALLOW))
369: quickexit(1);
370: auth_setenv(as);
371: if ((p = getenv("AUTH_TYPE")) != NULL &&
372: strncmp(p, "auth-", 5) == 0)
373: type = p;
374: if ((p = getenv("REMOTE_NAME")) != NULL)
375: hostname = p;
376: /*
377: * we may have changed some values, reset them
378: */
379: auth_clroptions(as);
380: if (type)
381: auth_setoption(as, "auth_type", type);
382: if (fqdn)
383: auth_setoption(as, "fqdn", fqdn);
384: if (hostname)
385: auth_setoption(as, "hostname", hostname);
386: if (lipaddr)
387: auth_setoption(as, "local_addr", lipaddr);
388: if (ripaddr)
389: auth_setoption(as, "remote_addr", ripaddr);
390: }
391:
392: /*
393: * Request the things like the approval script print things
394: * to stdout (in particular, the nologins files)
395: */
396: auth_setitem(as, AUTHV_INTERACTIVE, "True");
397:
1.1 deraadt 398: for (cnt = 0;; ask = 1) {
1.36 millert 399: /*
400: * Clean up our current authentication session.
401: * Options are not cleared so we need to clear any
402: * we might set below.
403: */
404: auth_clean(as);
405: auth_clroption(as, "style");
406: auth_clroption(as, "lastchance");
407:
408: lastchance = 0;
409:
1.1 deraadt 410: if (ask) {
411: fflag = 0;
412: getloginname();
413: }
1.36 millert 414: if (needto) {
415: needto = 0;
416: alarm(timeout);
417: }
1.47 deraadt 418: if ((style = strchr(username, ':')) != NULL)
1.36 millert 419: *style++ = '\0';
420: if (fullname)
421: free(fullname);
422: if (auth_setitem(as, AUTHV_NAME, username) < 0 ||
423: (fullname = strdup(username)) == NULL) {
424: syslog(LOG_ERR, "%m");
425: warn(NULL);
426: quickexit(1);
427: }
1.1 deraadt 428: rootlogin = 0;
1.55 millert 429: if ((instance = strchr(username, '/')) != NULL) {
1.40 millert 430: if (strncmp(instance + 1, "root", 4) == 0)
1.1 deraadt 431: rootlogin = 1;
432: *instance++ = '\0';
433: } else
434: instance = "";
1.36 millert 435:
1.1 deraadt 436: if (strlen(username) > UT_NAMESIZE)
437: username[UT_NAMESIZE] = '\0';
438:
439: /*
440: * Note if trying multiple user names; log failures for
441: * previous user name, but don't bother logging one failure
442: * for nonexistent name (mistyped username).
443: */
444: if (failures && strcmp(tbuf, username)) {
445: if (failures > (pwd ? 0 : 1))
446: badlogin(tbuf);
447: failures = 0;
448: }
1.36 millert 449: (void)strlcpy(tbuf, username, sizeof(tbuf));
1.1 deraadt 450:
1.36 millert 451: if ((pwd = getpwnam(username)) != NULL &&
452: auth_setpwd(as, pwd) < 0) {
453: syslog(LOG_ERR, "%m");
454: warn(NULL);
455: quickexit(1);
456: }
1.1 deraadt 457:
1.36 millert 458: lc = login_getclass(pwd ? pwd->pw_class : NULL);
459: if (!lc)
460: goto failed;
1.1 deraadt 461:
1.36 millert 462: style = login_getstyle(lc, style, type);
463: if (!style)
464: goto failed;
1.1 deraadt 465:
1.36 millert 466: /*
1.37 millert 467: * We allow "login-tries" attempts to login but start
468: * slowing down after "login-backoff" attempts.
469: */
470: tries = (int)login_getcapnum(lc, "login-tries", 10, 10);
471: backoff = (int)login_getcapnum(lc, "login-backoff", 3, 3);
472:
473: /*
1.36 millert 474: * Turn off the fflag if we have an an invalid user
475: * or we are not root and we are trying to change uids.
476: */
477: if (!pwd || (uid && uid != pwd->pw_uid))
478: fflag = 0;
1.1 deraadt 479:
1.36 millert 480: if (pwd && pwd->pw_uid == 0)
481: rootlogin = 1;
1.25 millert 482:
1.36 millert 483: /*
484: * If we do not have the force flag authenticate the user
485: */
1.44 millert 486: if (!fflag) {
1.36 millert 487: lastchance =
488: login_getcaptime(lc, "password-dead", 0, 0) != 0;
489: if (lastchance)
490: auth_setoption(as, "lastchance", "yes");
491: /*
492: * Once we start asking for a password
493: * we want to log a failure on a hup.
494: */
495: signal(SIGHUP, sighup);
496: auth_verify(as, style, NULL, lc->lc_class, NULL);
497: authok = auth_getstate(as);
498: /*
499: * If their password expired and it has not been
500: * too long since then, give the user one last
501: * chance to change their password
502: */
503: if ((authok & AUTH_PWEXPIRED) && lastchance) {
504: authok = AUTH_OKAY;
505: } else
506: lastchance = 0;
507: if ((authok & AUTH_ALLOW) == 0)
508: goto failed;
509: if (auth_setoption(as, "style", style) < 0) {
510: syslog(LOG_ERR, "%m");
511: warn(NULL);
512: quickexit(1);
1.25 millert 513: }
1.1 deraadt 514: }
1.36 millert 515: /*
516: * explicitly reject users without password file entries
517: */
1.47 deraadt 518: if (pwd == NULL)
1.36 millert 519: goto failed;
1.1 deraadt 520:
521: /*
1.36 millert 522: * If trying to log in as root on an insecure terminal,
523: * refuse the login attempt unless the authentication
524: * style explicitly says a root login is okay.
1.1 deraadt 525: */
1.44 millert 526: if (pwd && rootlogin && !rootterm(tty))
1.36 millert 527: goto failed;
1.29 millert 528:
1.36 millert 529: if (fflag) {
530: type = 0;
531: style = "forced";
532: }
533: break;
534:
535: failed:
536: if (authok & AUTH_SILENT)
537: quickexit(0);
1.29 millert 538: if (rootlogin && !rootterm(tty)) {
1.36 millert 539: warnx("%s login refused on this terminal.",
540: fullname);
1.1 deraadt 541: if (hostname)
542: syslog(LOG_NOTICE,
1.14 millert 543: "LOGIN %s REFUSED FROM %s%s%s ON TTY %s",
1.36 millert 544: fullname, rusername ? rusername : "",
1.14 millert 545: rusername ? "@" : "", hostname, tty);
1.1 deraadt 546: else
547: syslog(LOG_NOTICE,
548: "LOGIN %s REFUSED ON TTY %s",
1.47 deraadt 549: fullname, tty);
1.36 millert 550: } else {
551: if (!as || (p = auth_getvalue(as, "errormsg")) == NULL)
552: p = "Login incorrect";
553: (void)printf("%s\n", p);
554: }
1.1 deraadt 555: failures++;
1.13 millert 556: if (pwd)
1.14 millert 557: log_failedlogin(pwd->pw_uid, hostname, rusername, tty);
1.37 millert 558: /*
559: * By default, we allow 10 tries, but after 3 we start
560: * backing off to slow down password guessers.
561: */
562: if (++cnt > backoff) {
563: if (cnt >= tries) {
1.1 deraadt 564: badlogin(username);
565: sleepexit(1);
566: }
1.37 millert 567: sleep((u_int)((cnt - backoff) * tries / 2));
1.1 deraadt 568: }
569: }
570:
571: /* committed to login -- turn off timeout */
1.36 millert 572: (void)alarm(0);
1.1 deraadt 573:
574: endpwent();
575:
1.30 millert 576: shell = login_getcapstr(lc, "shell", pwd->pw_shell, pwd->pw_shell);
577: if (*shell == '\0')
578: shell = _PATH_BSHELL;
579: else if (strlen(shell) >= MAXPATHLEN) {
580: syslog(LOG_ERR, "shell path too long: %s", shell);
581: warnx("invalid shell");
1.36 millert 582: quickexit(1);
1.24 art 583: }
1.1 deraadt 584:
585: /* Destroy environment unless user has requested its preservation. */
1.24 art 586: if (!pflag) {
1.22 deraadt 587: if ((environ = calloc(1, sizeof (char *))) == NULL)
588: err(1, "calloc");
1.24 art 589: } else {
1.9 millert 590: char **cpp, **cpp2;
591:
592: for (cpp2 = cpp = environ; *cpp; cpp++) {
593: if (strncmp(*cpp, "LD_", 3) &&
1.29 millert 594: strncmp(*cpp, "ENV=", 4) &&
595: strncmp(*cpp, "BASH_ENV=", 9) &&
1.9 millert 596: strncmp(*cpp, "IFS=", 4))
597: *cpp2++ = *cpp;
598: }
599: *cpp2 = 0;
600: }
1.30 millert 601: /* Note: setusercontext(3) will set PATH */
1.34 deraadt 602: if (setenv("HOME", pwd->pw_dir, 1) == -1 ||
1.58 ! martynas 603: setenv("SHELL", pwd->pw_shell, 1) == -1) {
1.34 deraadt 604: warn("unable to setenv()");
1.36 millert 605: quickexit(1);
1.34 deraadt 606: }
1.1 deraadt 607: if (term[0] == '\0')
1.29 millert 608: (void)strlcpy(term, stypeof(tty), sizeof(term));
1.34 deraadt 609: if (setenv("TERM", term, 0) == -1 ||
610: setenv("LOGNAME", pwd->pw_name, 1) == -1 ||
611: setenv("USER", pwd->pw_name, 1) == -1) {
612: warn("unable to setenv()");
1.36 millert 613: quickexit(1);
1.34 deraadt 614: }
615: if (hostname) {
616: if (setenv("REMOTEHOST", hostname, 1) == -1) {
617: warn("unable to setenv()");
1.36 millert 618: quickexit(1);
1.34 deraadt 619: }
620: }
621: if (rusername) {
622: if (setenv("REMOTEUSER", rusername, 1) == -1) {
623: warn("unable to setenv()");
1.36 millert 624: quickexit(1);
1.34 deraadt 625: }
626: }
1.36 millert 627:
628: if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETPATH)) {
629: warn("unable to set user context");
630: quickexit(1);
631: }
632: auth_setenv(as);
633:
634: /* if user not super-user, check for disabled logins */
635: if (!rootlogin)
636: auth_checknologin(lc);
637:
638: setegid(pwd->pw_gid);
639: seteuid(pwd->pw_uid);
640:
641: homeless = chdir(pwd->pw_dir);
642: if (homeless) {
643: if (login_getcapbool(lc, "requirehome", 0)) {
644: (void)printf("No home directory %s!\n", pwd->pw_dir);
645: quickexit(1);
1.34 deraadt 646: }
1.36 millert 647: if (chdir("/"))
648: quickexit(0);
1.34 deraadt 649: }
1.36 millert 650:
651: quietlog = ((strcmp(pwd->pw_shell, "/sbin/nologin") == 0) ||
652: login_getcapbool(lc, "hushlogin", 0) ||
653: (access(_PATH_HUSHLOGIN, F_OK) == 0));
654:
655: seteuid(0);
656: setegid(0); /* XXX use a saved gid instead? */
657:
658: if ((p = auth_getvalue(as, "warnmsg")) != NULL)
659: (void)printf("WARNING: %s\n\n", p);
660:
661: expire = auth_check_expire(as);
662: if (expire < 0) {
663: (void)printf("Sorry -- your account has expired.\n");
664: quickexit(1);
665: } else if (expire > 0 && !quietlog) {
666: warning = login_getcaptime(lc, "expire-warn",
667: 2 * DAYSPERWEEK * SECSPERDAY, 2 * DAYSPERWEEK * SECSPERDAY);
668: if (expire < warning)
1.47 deraadt 669: (void)printf("Warning: your account expires on %s",
1.36 millert 670: ctime(&pwd->pw_expire));
1.34 deraadt 671: }
1.36 millert 672:
673: /* Nothing else left to fail -- really log in. */
674: (void)signal(SIGHUP, SIG_DFL);
675: memset(&utmp, 0, sizeof(utmp));
676: (void)time(&utmp.ut_time);
677: (void)strncpy(utmp.ut_name, username, sizeof(utmp.ut_name));
678: if (hostname)
679: (void)strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host));
680: (void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line));
681: login(&utmp);
682:
683: if (!quietlog)
684: (void)check_failedlogin(pwd->pw_uid);
685: dolastlog(quietlog);
686:
687: login_fbtab(tty, pwd->pw_uid, pwd->pw_gid);
688:
689: (void)chown(ttyn, pwd->pw_uid,
690: (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid);
691:
1.1 deraadt 692: /* If fflag is on, assume caller/authenticator has logged root login. */
1.24 art 693: if (rootlogin && fflag == 0) {
1.1 deraadt 694: if (hostname)
1.14 millert 695: syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s%s%s",
696: username, tty, rusername ? rusername : "",
697: rusername ? "@" : "", hostname);
1.1 deraadt 698: else
699: syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s", username, tty);
1.24 art 700: }
1.1 deraadt 701:
702: if (!quietlog) {
1.36 millert 703: if ((copyright =
704: login_getcapstr(lc, "copyright", NULL, NULL)) != NULL)
705: auth_cat(copyright);
1.1 deraadt 706: motd();
707: (void)snprintf(tbuf,
708: sizeof(tbuf), "%s/%s", _PATH_MAILDIR, pwd->pw_name);
709: if (stat(tbuf, &st) == 0 && st.st_size != 0)
710: (void)printf("You have %smail.\n",
711: (st.st_mtime > st.st_atime) ? "new " : "");
712: }
713:
714: (void)signal(SIGALRM, SIG_DFL);
715: (void)signal(SIGQUIT, SIG_DFL);
1.36 millert 716: (void)signal(SIGHUP, SIG_DFL);
1.1 deraadt 717: (void)signal(SIGINT, SIG_DFL);
718: (void)signal(SIGTSTP, SIG_IGN);
719:
720: tbuf[0] = '-';
1.30 millert 721: (void)strlcpy(tbuf + 1, (p = strrchr(shell, '/')) ?
1.36 millert 722: p + 1 : shell, sizeof(tbuf) - 1);
723:
724: if ((scds.rlim_cur != QUAD_MIN || scds.rlim_max != QUAD_MIN) &&
725: setrlimit(RLIMIT_CORE, &scds) < 0)
726: syslog(LOG_ERR, "couldn't reset core dump size: %m");
727:
728: if (lastchance)
1.47 deraadt 729: (void)printf("WARNING: Your password has expired."
730: " You must change your password, now!\n");
1.1 deraadt 731:
1.38 millert 732: if (setusercontext(lc, pwd, rootlogin ? 0 : pwd->pw_uid,
1.36 millert 733: LOGIN_SETALL & ~LOGIN_SETPATH) < 0) {
1.30 millert 734: warn("unable to set user context");
1.36 millert 735: quickexit(1);
736: }
737:
738: if (homeless) {
739: (void)printf("No home directory %s!\n", pwd->pw_dir);
740: (void)printf("Logging in with home = \"/\".\n");
741: (void)setenv("HOME", "/", 1);
1.15 tholo 742: }
1.30 millert 743:
1.36 millert 744: if (auth_approval(as, lc, NULL, "login") == 0) {
745: if (auth_getstate(as) & AUTH_EXPIRED)
746: (void)printf("Sorry -- your account has expired.\n");
747: else
748: (void)printf("approval failure\n");
749: quickexit(1);
750: }
751:
752: /*
753: * The last thing we do is discard all of the open file descriptors.
754: * Last because the C library may have some open.
755: */
1.53 deraadt 756: closefrom(STDERR_FILENO + 1);
1.36 millert 757:
758: /*
759: * Close the authentication session, make sure it is marked
760: * as okay so no files are removed.
761: */
762: auth_setstate(as, AUTH_OKAY);
763: auth_close(as);
764:
1.42 deraadt 765: execlp(shell, tbuf, (char *)NULL);
1.30 millert 766: err(1, "%s", shell);
1.1 deraadt 767: }
768:
769: /*
1.36 millert 770: * Allow for a '.' and 16 characters for any instance as well as
771: * space for a ':' and 16 charcters defining the authentication type.
1.1 deraadt 772: */
1.36 millert 773: #define NBUFSIZ (UT_NAMESIZE + 1 + 16 + 1 + 16)
1.1 deraadt 774:
775: void
1.47 deraadt 776: getloginname(void)
1.1 deraadt 777: {
1.47 deraadt 778: static char nbuf[NBUFSIZ], *p;
1.1 deraadt 779: int ch;
780:
781: for (;;) {
782: (void)printf("login: ");
783: for (p = nbuf; (ch = getchar()) != '\n'; ) {
784: if (ch == EOF) {
785: badlogin(username);
1.36 millert 786: quickexit(0);
1.1 deraadt 787: }
788: if (p < nbuf + (NBUFSIZ - 1))
789: *p++ = ch;
790: }
1.24 art 791: if (p > nbuf) {
1.1 deraadt 792: if (nbuf[0] == '-')
793: (void)fprintf(stderr,
794: "login names may not start with '-'.\n");
795: else {
796: *p = '\0';
797: username = nbuf;
798: break;
799: }
1.24 art 800: }
1.1 deraadt 801: }
802: }
803:
804: int
1.47 deraadt 805: rootterm(char *ttyn)
1.1 deraadt 806: {
807: struct ttyent *t;
808:
1.36 millert 809: /* XXX - stash output of getttynam() elsewhere */
1.1 deraadt 810: return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE);
811: }
812:
813: void
1.47 deraadt 814: motd(void)
1.1 deraadt 815: {
1.47 deraadt 816: char tbuf[8192], *motd;
1.1 deraadt 817: int fd, nchars;
1.48 millert 818: struct sigaction sa, osa;
1.30 millert 819:
820: motd = login_getcapstr(lc, "welcome", _PATH_MOTDFILE, _PATH_MOTDFILE);
1.1 deraadt 821:
1.30 millert 822: if ((fd = open(motd, O_RDONLY, 0)) < 0)
1.1 deraadt 823: return;
1.48 millert 824:
825: memset(&sa, 0, sizeof(sa));
826: sa.sa_handler = sigint;
827: sigemptyset(&sa.sa_mask);
828: sa.sa_flags = 0; /* don't set SA_RESTART */
829: (void)sigaction(SIGINT, &sa, &osa);
830:
831: /* read and spew motd until EOF, error, or SIGINT */
832: while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0 &&
833: write(STDOUT_FILENO, tbuf, nchars) == nchars)
834: ;
835:
836: (void)sigaction(SIGINT, &osa, NULL);
1.1 deraadt 837: (void)close(fd);
838: }
839:
840: /* ARGSUSED */
841: void
1.47 deraadt 842: sigint(int signo)
1.1 deraadt 843: {
1.52 otto 844: return; /* just interrupt syscall */
1.1 deraadt 845: }
846:
847: /* ARGSUSED */
848: void
1.47 deraadt 849: timedout(int signo)
1.1 deraadt 850: {
1.47 deraadt 851: char warn[1024];
852:
853: snprintf(warn, sizeof warn,
854: "Login timed out after %d seconds\n", timeout);
855: write(STDERR_FILENO, warn, strlen(warn));
1.37 millert 856: if (username)
857: badlogin(username);
1.47 deraadt 858: _exit(0);
1.1 deraadt 859: }
860:
861: void
1.47 deraadt 862: dolastlog(int quiet)
1.1 deraadt 863: {
864: struct lastlog ll;
865: int fd;
866:
867: if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) >= 0) {
1.26 millert 868: (void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), SEEK_SET);
1.1 deraadt 869: if (!quiet) {
870: if (read(fd, (char *)&ll, sizeof(ll)) == sizeof(ll) &&
871: ll.ll_time != 0) {
872: (void)printf("Last login: %.*s ",
873: 24-5, (char *)ctime(&ll.ll_time));
1.14 millert 874: (void)printf("on %.*s",
875: (int)sizeof(ll.ll_line),
876: ll.ll_line);
1.1 deraadt 877: if (*ll.ll_host != '\0')
1.14 millert 878: (void)printf(" from %.*s",
1.1 deraadt 879: (int)sizeof(ll.ll_host),
880: ll.ll_host);
1.14 millert 881: (void)putchar('\n');
1.1 deraadt 882: }
1.26 millert 883: (void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll),
884: SEEK_SET);
1.1 deraadt 885: }
886: memset((void *)&ll, 0, sizeof(ll));
887: (void)time(&ll.ll_time);
888: (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line));
889: if (hostname)
890: (void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host));
891: (void)write(fd, (char *)&ll, sizeof(ll));
892: (void)close(fd);
893: }
894: }
895:
896: void
1.47 deraadt 897: badlogin(char *name)
1.1 deraadt 898: {
1.47 deraadt 899: struct syslog_data sdata = SYSLOG_DATA_INIT;
900:
1.1 deraadt 901: if (failures == 0)
902: return;
903: if (hostname) {
1.47 deraadt 904: syslog_r(LOG_NOTICE, &sdata,
905: "%d LOGIN FAILURE%s FROM %s%s%s",
1.14 millert 906: failures, failures > 1 ? "S" : "",
907: rusername ? rusername : "", rusername ? "@" : "", hostname);
1.47 deraadt 908: syslog_r(LOG_AUTHPRIV|LOG_NOTICE, &sdata,
1.14 millert 909: "%d LOGIN FAILURE%s FROM %s%s%s, %s",
910: failures, failures > 1 ? "S" : "",
911: rusername ? rusername : "", rusername ? "@" : "",
912: hostname, name);
1.1 deraadt 913: } else {
1.47 deraadt 914: syslog_r(LOG_NOTICE, &sdata,
915: "%d LOGIN FAILURE%s ON %s",
1.1 deraadt 916: failures, failures > 1 ? "S" : "", tty);
1.47 deraadt 917: syslog_r(LOG_AUTHPRIV|LOG_NOTICE, &sdata,
1.1 deraadt 918: "%d LOGIN FAILURE%s ON %s, %s",
919: failures, failures > 1 ? "S" : "", tty, name);
920: }
921: }
922:
923: #undef UNKNOWN
924: #define UNKNOWN "su"
925:
926: char *
1.47 deraadt 927: stypeof(char *ttyid)
1.1 deraadt 928: {
929: struct ttyent *t;
930:
1.30 millert 931: return (ttyid && (t = getttynam(ttyid)) ? t->ty_type :
932: login_getcapstr(lc, "term", UNKNOWN, UNKNOWN));
1.1 deraadt 933: }
934:
935: void
1.47 deraadt 936: sleepexit(int eval)
1.1 deraadt 937: {
1.36 millert 938: auth_close(as);
1.1 deraadt 939: (void)sleep(5);
940: exit(eval);
1.11 millert 941: }
942:
943: void
1.47 deraadt 944: quickexit(int eval)
1.36 millert 945: {
946: if (as)
947: auth_close(as);
948: exit(eval);
949: }
950:
951:
952: void
1.47 deraadt 953: sighup(int signum)
1.11 millert 954: {
955: if (username)
956: badlogin(username);
1.47 deraadt 957: _exit(0);
1.1 deraadt 958: }