xref: /dragonfly/crypto/openssh/loginrec.c (revision 81c11cd3)
1 /*
2  * Copyright (c) 2000 Andre Lucas.  All rights reserved.
3  * Portions copyright (c) 1998 Todd C. Miller
4  * Portions copyright (c) 1996 Jason Downs
5  * Portions copyright (c) 1996 Theo de Raadt
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 /*
29  * The btmp logging code is derived from login.c from util-linux and is under
30  * the the following license:
31  *
32  * Copyright (c) 1980, 1987, 1988 The Regents of the University of California.
33  * All rights reserved.
34  *
35  * Redistribution and use in source and binary forms are permitted
36  * provided that the above copyright notice and this paragraph are
37  * duplicated in all such forms and that any documentation,
38  * advertising materials, and other materials related to such
39  * distribution and use acknowledge that the software was developed
40  * by the University of California, Berkeley.  The name of the
41  * University may not be used to endorse or promote products derived
42  * from this software without specific prior written permission.
43  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
44  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
45  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
46  */
47 
48 
49 /**
50  ** loginrec.c:  platform-independent login recording and lastlog retrieval
51  **/
52 
53 /*
54  *  The new login code explained
55  *  ============================
56  *
57  *  This code attempts to provide a common interface to login recording
58  *  (utmp and friends) and last login time retrieval.
59  *
60  *  Its primary means of achieving this is to use 'struct logininfo', a
61  *  union of all the useful fields in the various different types of
62  *  system login record structures one finds on UNIX variants.
63  *
64  *  We depend on autoconf to define which recording methods are to be
65  *  used, and which fields are contained in the relevant data structures
66  *  on the local system. Many C preprocessor symbols affect which code
67  *  gets compiled here.
68  *
69  *  The code is designed to make it easy to modify a particular
70  *  recording method, without affecting other methods nor requiring so
71  *  many nested conditional compilation blocks as were commonplace in
72  *  the old code.
73  *
74  *  For login recording, we try to use the local system's libraries as
75  *  these are clearly most likely to work correctly. For utmp systems
76  *  this usually means login() and logout() or setutent() etc., probably
77  *  in libutil, along with logwtmp() etc. On these systems, we fall back
78  *  to writing the files directly if we have to, though this method
79  *  requires very thorough testing so we do not corrupt local auditing
80  *  information. These files and their access methods are very system
81  *  specific indeed.
82  *
83  *  For utmpx systems, the corresponding library functions are
84  *  setutxent() etc. To the author's knowledge, all utmpx systems have
85  *  these library functions and so no direct write is attempted. If such
86  *  a system exists and needs support, direct analogues of the [uw]tmp
87  *  code should suffice.
88  *
89  *  Retrieving the time of last login ('lastlog') is in some ways even
90  *  more problemmatic than login recording. Some systems provide a
91  *  simple table of all users which we seek based on uid and retrieve a
92  *  relatively standard structure. Others record the same information in
93  *  a directory with a separate file, and others don't record the
94  *  information separately at all. For systems in the latter category,
95  *  we look backwards in the wtmp or wtmpx file for the last login entry
96  *  for our user. Naturally this is slower and on busy systems could
97  *  incur a significant performance penalty.
98  *
99  *  Calling the new code
100  *  --------------------
101  *
102  *  In OpenSSH all login recording and retrieval is performed in
103  *  login.c. Here you'll find working examples. Also, in the logintest.c
104  *  program there are more examples.
105  *
106  *  Internal handler calling method
107  *  -------------------------------
108  *
109  *  When a call is made to login_login() or login_logout(), both
110  *  routines set a struct logininfo flag defining which action (log in,
111  *  or log out) is to be taken. They both then call login_write(), which
112  *  calls whichever of the many structure-specific handlers autoconf
113  *  selects for the local system.
114  *
115  *  The handlers themselves handle system data structure specifics. Both
116  *  struct utmp and struct utmpx have utility functions (see
117  *  construct_utmp*()) to try to make it simpler to add extra systems
118  *  that introduce new features to either structure.
119  *
120  *  While it may seem terribly wasteful to replicate so much similar
121  *  code for each method, experience has shown that maintaining code to
122  *  write both struct utmp and utmpx in one function, whilst maintaining
123  *  support for all systems whether they have library support or not, is
124  *  a difficult and time-consuming task.
125  *
126  *  Lastlog support proceeds similarly. Functions login_get_lastlog()
127  *  (and its OpenSSH-tuned friend login_get_lastlog_time()) call
128  *  getlast_entry(), which tries one of three methods to find the last
129  *  login time. It uses local system lastlog support if it can,
130  *  otherwise it tries wtmp or wtmpx before giving up and returning 0,
131  *  meaning "tilt".
132  *
133  *  Maintenance
134  *  -----------
135  *
136  *  In many cases it's possible to tweak autoconf to select the correct
137  *  methods for a particular platform, either by improving the detection
138  *  code (best), or by presetting DISABLE_<method> or CONF_<method>_FILE
139  *  symbols for the platform.
140  *
141  *  Use logintest to check which symbols are defined before modifying
142  *  configure.ac and loginrec.c. (You have to build logintest yourself
143  *  with 'make logintest' as it's not built by default.)
144  *
145  *  Otherwise, patches to the specific method(s) are very helpful!
146  */
147 
148 #include "includes.h"
149 
150 #include <sys/types.h>
151 #include <sys/stat.h>
152 #include <sys/socket.h>
153 
154 #include <netinet/in.h>
155 
156 #include <errno.h>
157 #include <fcntl.h>
158 #ifdef HAVE_PATHS_H
159 # include <paths.h>
160 #endif
161 #include <pwd.h>
162 #include <stdarg.h>
163 #include <string.h>
164 #include <time.h>
165 #include <unistd.h>
166 
167 #include "xmalloc.h"
168 #include "key.h"
169 #include "hostfile.h"
170 #include "ssh.h"
171 #include "loginrec.h"
172 #include "log.h"
173 #include "atomicio.h"
174 #include "packet.h"
175 #include "canohost.h"
176 #include "auth.h"
177 #include "buffer.h"
178 
179 #ifdef HAVE_UTIL_H
180 # include <util.h>
181 #endif
182 
183 #ifdef HAVE_LIBUTIL_H
184 # include <libutil.h>
185 #endif
186 
187 /**
188  ** prototypes for helper functions in this file
189  **/
190 
191 #if HAVE_UTMP_H
192 void set_utmp_time(struct logininfo *li, struct utmp *ut);
193 void construct_utmp(struct logininfo *li, struct utmp *ut);
194 #endif
195 
196 #ifdef HAVE_UTMPX_H
197 void set_utmpx_time(struct logininfo *li, struct utmpx *ut);
198 void construct_utmpx(struct logininfo *li, struct utmpx *ut);
199 #endif
200 
201 int utmp_write_entry(struct logininfo *li);
202 int utmpx_write_entry(struct logininfo *li);
203 int wtmp_write_entry(struct logininfo *li);
204 int wtmpx_write_entry(struct logininfo *li);
205 int lastlog_write_entry(struct logininfo *li);
206 int syslogin_write_entry(struct logininfo *li);
207 
208 int getlast_entry(struct logininfo *li);
209 int lastlog_get_entry(struct logininfo *li);
210 int utmpx_get_entry(struct logininfo *li);
211 int wtmp_get_entry(struct logininfo *li);
212 int wtmpx_get_entry(struct logininfo *li);
213 
214 extern Buffer loginmsg;
215 
216 /* pick the shortest string */
217 #define MIN_SIZEOF(s1,s2) (sizeof(s1) < sizeof(s2) ? sizeof(s1) : sizeof(s2))
218 
219 /**
220  ** platform-independent login functions
221  **/
222 
223 /*
224  * login_login(struct logininfo *) - Record a login
225  *
226  * Call with a pointer to a struct logininfo initialised with
227  * login_init_entry() or login_alloc_entry()
228  *
229  * Returns:
230  *  >0 if successful
231  *  0  on failure (will use OpenSSH's logging facilities for diagnostics)
232  */
233 int
234 login_login(struct logininfo *li)
235 {
236 	li->type = LTYPE_LOGIN;
237 	return (login_write(li));
238 }
239 
240 
241 /*
242  * login_logout(struct logininfo *) - Record a logout
243  *
244  * Call as with login_login()
245  *
246  * Returns:
247  *  >0 if successful
248  *  0  on failure (will use OpenSSH's logging facilities for diagnostics)
249  */
250 int
251 login_logout(struct logininfo *li)
252 {
253 	li->type = LTYPE_LOGOUT;
254 	return (login_write(li));
255 }
256 
257 /*
258  * login_get_lastlog_time(int) - Retrieve the last login time
259  *
260  * Retrieve the last login time for the given uid. Will try to use the
261  * system lastlog facilities if they are available, but will fall back
262  * to looking in wtmp/wtmpx if necessary
263  *
264  * Returns:
265  *   0 on failure, or if user has never logged in
266  *   Time in seconds from the epoch if successful
267  *
268  * Useful preprocessor symbols:
269  *   DISABLE_LASTLOG: If set, *never* even try to retrieve lastlog
270  *                    info
271  *   USE_LASTLOG: If set, indicates the presence of system lastlog
272  *                facilities. If this and DISABLE_LASTLOG are not set,
273  *                try to retrieve lastlog information from wtmp/wtmpx.
274  */
275 unsigned int
276 login_get_lastlog_time(const int uid)
277 {
278 	struct logininfo li;
279 
280 	if (login_get_lastlog(&li, uid))
281 		return (li.tv_sec);
282 	else
283 		return (0);
284 }
285 
286 /*
287  * login_get_lastlog(struct logininfo *, int)   - Retrieve a lastlog entry
288  *
289  * Retrieve a logininfo structure populated (only partially) with
290  * information from the system lastlog data, or from wtmp/wtmpx if no
291  * system lastlog information exists.
292  *
293  * Note this routine must be given a pre-allocated logininfo.
294  *
295  * Returns:
296  *  >0: A pointer to your struct logininfo if successful
297  *  0  on failure (will use OpenSSH's logging facilities for diagnostics)
298  */
299 struct logininfo *
300 login_get_lastlog(struct logininfo *li, const int uid)
301 {
302 	struct passwd *pw;
303 
304 	memset(li, '\0', sizeof(*li));
305 	li->uid = uid;
306 
307 	/*
308 	 * If we don't have a 'real' lastlog, we need the username to
309 	 * reliably search wtmp(x) for the last login (see
310 	 * wtmp_get_entry().)
311 	 */
312 	pw = getpwuid(uid);
313 	if (pw == NULL)
314 		fatal("%s: Cannot find account for uid %i", __func__, uid);
315 
316 	/* No MIN_SIZEOF here - we absolutely *must not* truncate the
317 	 * username (XXX - so check for trunc!) */
318 	strlcpy(li->username, pw->pw_name, sizeof(li->username));
319 
320 	if (getlast_entry(li))
321 		return (li);
322 	else
323 		return (NULL);
324 }
325 
326 
327 /*
328  * login_alloc_entry(int, char*, char*, char*)    - Allocate and initialise
329  *                                                  a logininfo structure
330  *
331  * This function creates a new struct logininfo, a data structure
332  * meant to carry the information required to portably record login info.
333  *
334  * Returns a pointer to a newly created struct logininfo. If memory
335  * allocation fails, the program halts.
336  */
337 struct
338 logininfo *login_alloc_entry(int pid, const char *username,
339     const char *hostname, const char *line)
340 {
341 	struct logininfo *newli;
342 
343 	newli = xmalloc(sizeof(*newli));
344 	login_init_entry(newli, pid, username, hostname, line);
345 	return (newli);
346 }
347 
348 
349 /* login_free_entry(struct logininfo *)    - free struct memory */
350 void
351 login_free_entry(struct logininfo *li)
352 {
353 	xfree(li);
354 }
355 
356 
357 /* login_init_entry(struct logininfo *, int, char*, char*, char*)
358  *                                        - initialise a struct logininfo
359  *
360  * Populates a new struct logininfo, a data structure meant to carry
361  * the information required to portably record login info.
362  *
363  * Returns: 1
364  */
365 int
366 login_init_entry(struct logininfo *li, int pid, const char *username,
367     const char *hostname, const char *line)
368 {
369 	struct passwd *pw;
370 
371 	memset(li, 0, sizeof(*li));
372 
373 	li->pid = pid;
374 
375 	/* set the line information */
376 	if (line)
377 		line_fullname(li->line, line, sizeof(li->line));
378 
379 	if (username) {
380 		strlcpy(li->username, username, sizeof(li->username));
381 		pw = getpwnam(li->username);
382 		if (pw == NULL) {
383 			fatal("%s: Cannot find user \"%s\"", __func__,
384 			    li->username);
385 		}
386 		li->uid = pw->pw_uid;
387 	}
388 
389 	if (hostname)
390 		strlcpy(li->hostname, hostname, sizeof(li->hostname));
391 
392 	return (1);
393 }
394 
395 /*
396  * login_set_current_time(struct logininfo *)    - set the current time
397  *
398  * Set the current time in a logininfo structure. This function is
399  * meant to eliminate the need to deal with system dependencies for
400  * time handling.
401  */
402 void
403 login_set_current_time(struct logininfo *li)
404 {
405 	struct timeval tv;
406 
407 	gettimeofday(&tv, NULL);
408 
409 	li->tv_sec = tv.tv_sec;
410 	li->tv_usec = tv.tv_usec;
411 }
412 
413 /* copy a sockaddr_* into our logininfo */
414 void
415 login_set_addr(struct logininfo *li, const struct sockaddr *sa,
416     const unsigned int sa_size)
417 {
418 	unsigned int bufsize = sa_size;
419 
420 	/* make sure we don't overrun our union */
421 	if (sizeof(li->hostaddr) < sa_size)
422 		bufsize = sizeof(li->hostaddr);
423 
424 	memcpy(&li->hostaddr.sa, sa, bufsize);
425 }
426 
427 
428 /**
429  ** login_write: Call low-level recording functions based on autoconf
430  ** results
431  **/
432 int
433 login_write(struct logininfo *li)
434 {
435 #ifndef HAVE_CYGWIN
436 	if (geteuid() != 0) {
437 		logit("Attempt to write login records by non-root user (aborting)");
438 		return (1);
439 	}
440 #endif
441 
442 	/* set the timestamp */
443 	login_set_current_time(li);
444 #ifdef USE_LOGIN
445 	syslogin_write_entry(li);
446 #endif
447 #ifdef USE_LASTLOG
448 	if (li->type == LTYPE_LOGIN)
449 		lastlog_write_entry(li);
450 #endif
451 #ifdef USE_UTMP
452 	utmp_write_entry(li);
453 #endif
454 #ifdef USE_WTMP
455 	wtmp_write_entry(li);
456 #endif
457 #ifdef USE_UTMPX
458 	utmpx_write_entry(li);
459 #endif
460 #ifdef USE_WTMPX
461 	wtmpx_write_entry(li);
462 #endif
463 #ifdef CUSTOM_SYS_AUTH_RECORD_LOGIN
464 	if (li->type == LTYPE_LOGIN &&
465 	    !sys_auth_record_login(li->username,li->hostname,li->line,
466 	    &loginmsg))
467 		logit("Writing login record failed for %s", li->username);
468 #endif
469 #ifdef SSH_AUDIT_EVENTS
470 	if (li->type == LTYPE_LOGIN)
471 		audit_session_open(li->line);
472 	else if (li->type == LTYPE_LOGOUT)
473 		audit_session_close(li->line);
474 #endif
475 	return (0);
476 }
477 
478 #ifdef LOGIN_NEEDS_UTMPX
479 int
480 login_utmp_only(struct logininfo *li)
481 {
482 	li->type = LTYPE_LOGIN;
483 	login_set_current_time(li);
484 # ifdef USE_UTMP
485 	utmp_write_entry(li);
486 # endif
487 # ifdef USE_WTMP
488 	wtmp_write_entry(li);
489 # endif
490 # ifdef USE_UTMPX
491 	utmpx_write_entry(li);
492 # endif
493 # ifdef USE_WTMPX
494 	wtmpx_write_entry(li);
495 # endif
496 	return (0);
497 }
498 #endif
499 
500 /**
501  ** getlast_entry: Call low-level functions to retrieve the last login
502  **                time.
503  **/
504 
505 /* take the uid in li and return the last login time */
506 int
507 getlast_entry(struct logininfo *li)
508 {
509 #ifdef USE_LASTLOG
510 	return(lastlog_get_entry(li));
511 #else /* !USE_LASTLOG */
512 #if defined(USE_UTMPX) && defined(HAVE_SETUTXDB) && \
513     defined(UTXDB_LASTLOGIN) && defined(HAVE_GETUTXUSER)
514 	return (utmpx_get_entry(li));
515 #endif
516 
517 #if defined(DISABLE_LASTLOG)
518 	/* On some systems we shouldn't even try to obtain last login
519 	 * time, e.g. AIX */
520 	return (0);
521 # elif defined(USE_WTMP) && \
522     (defined(HAVE_TIME_IN_UTMP) || defined(HAVE_TV_IN_UTMP))
523 	/* retrieve last login time from utmp */
524 	return (wtmp_get_entry(li));
525 # elif defined(USE_WTMPX) && \
526     (defined(HAVE_TIME_IN_UTMPX) || defined(HAVE_TV_IN_UTMPX))
527 	/* If wtmp isn't available, try wtmpx */
528 	return (wtmpx_get_entry(li));
529 # else
530 	/* Give up: No means of retrieving last login time */
531 	return (0);
532 # endif /* DISABLE_LASTLOG */
533 #endif /* USE_LASTLOG */
534 }
535 
536 
537 
538 /*
539  * 'line' string utility functions
540  *
541  * These functions process the 'line' string into one of three forms:
542  *
543  * 1. The full filename (including '/dev')
544  * 2. The stripped name (excluding '/dev')
545  * 3. The abbreviated name (e.g. /dev/ttyp00 -> yp00
546  *                               /dev/pts/1  -> ts/1 )
547  *
548  * Form 3 is used on some systems to identify a .tmp.? entry when
549  * attempting to remove it. Typically both addition and removal is
550  * performed by one application - say, sshd - so as long as the choice
551  * uniquely identifies a terminal it's ok.
552  */
553 
554 
555 /*
556  * line_fullname(): add the leading '/dev/' if it doesn't exist make
557  * sure dst has enough space, if not just copy src (ugh)
558  */
559 char *
560 line_fullname(char *dst, const char *src, u_int dstsize)
561 {
562 	memset(dst, '\0', dstsize);
563 	if ((strncmp(src, "/dev/", 5) == 0) || (dstsize < (strlen(src) + 5)))
564 		strlcpy(dst, src, dstsize);
565 	else {
566 		strlcpy(dst, "/dev/", dstsize);
567 		strlcat(dst, src, dstsize);
568 	}
569 	return (dst);
570 }
571 
572 /* line_stripname(): strip the leading '/dev' if it exists, return dst */
573 char *
574 line_stripname(char *dst, const char *src, int dstsize)
575 {
576 	memset(dst, '\0', dstsize);
577 	if (strncmp(src, "/dev/", 5) == 0)
578 		strlcpy(dst, src + 5, dstsize);
579 	else
580 		strlcpy(dst, src, dstsize);
581 	return (dst);
582 }
583 
584 /*
585  * line_abbrevname(): Return the abbreviated (usually four-character)
586  * form of the line (Just use the last <dstsize> characters of the
587  * full name.)
588  *
589  * NOTE: use strncpy because we do NOT necessarily want zero
590  * termination
591  */
592 char *
593 line_abbrevname(char *dst, const char *src, int dstsize)
594 {
595 	size_t len;
596 
597 	memset(dst, '\0', dstsize);
598 
599 	/* Always skip prefix if present */
600 	if (strncmp(src, "/dev/", 5) == 0)
601 		src += 5;
602 
603 #ifdef WITH_ABBREV_NO_TTY
604 	if (strncmp(src, "tty", 3) == 0)
605 		src += 3;
606 #endif
607 
608 	len = strlen(src);
609 
610 	if (len > 0) {
611 		if (((int)len - dstsize) > 0)
612 			src +=  ((int)len - dstsize);
613 
614 		/* note: _don't_ change this to strlcpy */
615 		strncpy(dst, src, (size_t)dstsize);
616 	}
617 
618 	return (dst);
619 }
620 
621 /**
622  ** utmp utility functions
623  **
624  ** These functions manipulate struct utmp, taking system differences
625  ** into account.
626  **/
627 
628 #if defined(USE_UTMP) || defined (USE_WTMP) || defined (USE_LOGIN)
629 
630 /* build the utmp structure */
631 void
632 set_utmp_time(struct logininfo *li, struct utmp *ut)
633 {
634 # if defined(HAVE_TV_IN_UTMP)
635 	ut->ut_tv.tv_sec = li->tv_sec;
636 	ut->ut_tv.tv_usec = li->tv_usec;
637 # elif defined(HAVE_TIME_IN_UTMP)
638 	ut->ut_time = li->tv_sec;
639 # endif
640 }
641 
642 void
643 construct_utmp(struct logininfo *li,
644 		    struct utmp *ut)
645 {
646 # ifdef HAVE_ADDR_V6_IN_UTMP
647 	struct sockaddr_in6 *sa6;
648 # endif
649 
650 	memset(ut, '\0', sizeof(*ut));
651 
652 	/* First fill out fields used for both logins and logouts */
653 
654 # ifdef HAVE_ID_IN_UTMP
655 	line_abbrevname(ut->ut_id, li->line, sizeof(ut->ut_id));
656 # endif
657 
658 # ifdef HAVE_TYPE_IN_UTMP
659 	/* This is done here to keep utmp constants out of struct logininfo */
660 	switch (li->type) {
661 	case LTYPE_LOGIN:
662 		ut->ut_type = USER_PROCESS;
663 #ifdef _UNICOS
664 		cray_set_tmpdir(ut);
665 #endif
666 		break;
667 	case LTYPE_LOGOUT:
668 		ut->ut_type = DEAD_PROCESS;
669 #ifdef _UNICOS
670 		cray_retain_utmp(ut, li->pid);
671 #endif
672 		break;
673 	}
674 # endif
675 	set_utmp_time(li, ut);
676 
677 	line_stripname(ut->ut_line, li->line, sizeof(ut->ut_line));
678 
679 # ifdef HAVE_PID_IN_UTMP
680 	ut->ut_pid = li->pid;
681 # endif
682 
683 	/* If we're logging out, leave all other fields blank */
684 	if (li->type == LTYPE_LOGOUT)
685 		return;
686 
687 	/*
688 	 * These fields are only used when logging in, and are blank
689 	 * for logouts.
690 	 */
691 
692 	/* Use strncpy because we don't necessarily want null termination */
693 	strncpy(ut->ut_name, li->username,
694 	    MIN_SIZEOF(ut->ut_name, li->username));
695 # ifdef HAVE_HOST_IN_UTMP
696 	realhostname_sa(ut->ut_host, sizeof ut->ut_host,
697 	    &li->hostaddr.sa, li->hostaddr.sa.sa_len);
698 # endif
699 # ifdef HAVE_ADDR_IN_UTMP
700 	/* this is just a 32-bit IP address */
701 	if (li->hostaddr.sa.sa_family == AF_INET)
702 		ut->ut_addr = li->hostaddr.sa_in.sin_addr.s_addr;
703 # endif
704 # ifdef HAVE_ADDR_V6_IN_UTMP
705 	/* this is just a 128-bit IPv6 address */
706 	if (li->hostaddr.sa.sa_family == AF_INET6) {
707 		sa6 = ((struct sockaddr_in6 *)&li->hostaddr.sa);
708 		memcpy(ut->ut_addr_v6, sa6->sin6_addr.s6_addr, 16);
709 		if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr)) {
710 			ut->ut_addr_v6[0] = ut->ut_addr_v6[3];
711 			ut->ut_addr_v6[1] = 0;
712 			ut->ut_addr_v6[2] = 0;
713 			ut->ut_addr_v6[3] = 0;
714 		}
715 	}
716 # endif
717 }
718 #endif /* USE_UTMP || USE_WTMP || USE_LOGIN */
719 
720 /**
721  ** utmpx utility functions
722  **
723  ** These functions manipulate struct utmpx, accounting for system
724  ** variations.
725  **/
726 
727 #if defined(USE_UTMPX) || defined (USE_WTMPX)
728 /* build the utmpx structure */
729 void
730 set_utmpx_time(struct logininfo *li, struct utmpx *utx)
731 {
732 # if defined(HAVE_TV_IN_UTMPX)
733 	utx->ut_tv.tv_sec = li->tv_sec;
734 	utx->ut_tv.tv_usec = li->tv_usec;
735 # elif defined(HAVE_TIME_IN_UTMPX)
736 	utx->ut_time = li->tv_sec;
737 # endif
738 }
739 
740 void
741 construct_utmpx(struct logininfo *li, struct utmpx *utx)
742 {
743 # ifdef HAVE_ADDR_V6_IN_UTMP
744 	struct sockaddr_in6 *sa6;
745 #  endif
746 	memset(utx, '\0', sizeof(*utx));
747 
748 # ifdef HAVE_ID_IN_UTMPX
749 	line_abbrevname(utx->ut_id, li->line, sizeof(utx->ut_id));
750 # endif
751 
752 	/* this is done here to keep utmp constants out of loginrec.h */
753 	switch (li->type) {
754 	case LTYPE_LOGIN:
755 		utx->ut_type = USER_PROCESS;
756 		break;
757 	case LTYPE_LOGOUT:
758 		utx->ut_type = DEAD_PROCESS;
759 		break;
760 	}
761 	line_stripname(utx->ut_line, li->line, sizeof(utx->ut_line));
762 	set_utmpx_time(li, utx);
763 	utx->ut_pid = li->pid;
764 
765 	/* strncpy(): Don't necessarily want null termination */
766 	strncpy(utx->ut_user, li->username,
767 	    MIN_SIZEOF(utx->ut_user, li->username));
768 
769 	if (li->type == LTYPE_LOGOUT)
770 		return;
771 
772 	/*
773 	 * These fields are only used when logging in, and are blank
774 	 * for logouts.
775 	 */
776 
777 # ifdef HAVE_HOST_IN_UTMPX
778 	strncpy(utx->ut_host, li->hostname,
779 	    MIN_SIZEOF(utx->ut_host, li->hostname));
780 # endif
781 # ifdef HAVE_ADDR_IN_UTMPX
782 	/* this is just a 32-bit IP address */
783 	if (li->hostaddr.sa.sa_family == AF_INET)
784 		utx->ut_addr = li->hostaddr.sa_in.sin_addr.s_addr;
785 # endif
786 # ifdef HAVE_ADDR_V6_IN_UTMP
787 	/* this is just a 128-bit IPv6 address */
788 	if (li->hostaddr.sa.sa_family == AF_INET6) {
789 		sa6 = ((struct sockaddr_in6 *)&li->hostaddr.sa);
790 		memcpy(ut->ut_addr_v6, sa6->sin6_addr.s6_addr, 16);
791 		if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr)) {
792 			ut->ut_addr_v6[0] = ut->ut_addr_v6[3];
793 			ut->ut_addr_v6[1] = 0;
794 			ut->ut_addr_v6[2] = 0;
795 			ut->ut_addr_v6[3] = 0;
796 		}
797 	}
798 # endif
799 # ifdef HAVE_SYSLEN_IN_UTMPX
800 	/* ut_syslen is the length of the utx_host string */
801 	utx->ut_syslen = MIN(strlen(li->hostname), sizeof(utx->ut_host));
802 # endif
803 }
804 #endif /* USE_UTMPX || USE_WTMPX */
805 
806 /**
807  ** Low-level utmp functions
808  **/
809 
810 /* FIXME: (ATL) utmp_write_direct needs testing */
811 #ifdef USE_UTMP
812 
813 /* if we can, use pututline() etc. */
814 # if !defined(DISABLE_PUTUTLINE) && defined(HAVE_SETUTENT) && \
815 	defined(HAVE_PUTUTLINE)
816 #  define UTMP_USE_LIBRARY
817 # endif
818 
819 
820 /* write a utmp entry with the system's help (pututline() and pals) */
821 # ifdef UTMP_USE_LIBRARY
822 static int
823 utmp_write_library(struct logininfo *li, struct utmp *ut)
824 {
825 	setutent();
826 	pututline(ut);
827 #  ifdef HAVE_ENDUTENT
828 	endutent();
829 #  endif
830 	return (1);
831 }
832 # else /* UTMP_USE_LIBRARY */
833 
834 /*
835  * Write a utmp entry direct to the file
836  * This is a slightly modification of code in OpenBSD's login.c
837  */
838 static int
839 utmp_write_direct(struct logininfo *li, struct utmp *ut)
840 {
841 	struct utmp old_ut;
842 	register int fd;
843 	int tty;
844 
845 	/* FIXME: (ATL) ttyslot() needs local implementation */
846 
847 #if defined(HAVE_GETTTYENT)
848 	struct ttyent *ty;
849 
850 	tty=0;
851 	setttyent();
852 	while (NULL != (ty = getttyent())) {
853 		tty++;
854 		if (!strncmp(ty->ty_name, ut->ut_line, sizeof(ut->ut_line)))
855 			break;
856 	}
857 	endttyent();
858 
859 	if (NULL == ty) {
860 		logit("%s: tty not found", __func__);
861 		return (0);
862 	}
863 #else /* FIXME */
864 
865 	tty = ttyslot(); /* seems only to work for /dev/ttyp? style names */
866 
867 #endif /* HAVE_GETTTYENT */
868 
869 	if (tty > 0 && (fd = open(UTMP_FILE, O_RDWR|O_CREAT, 0644)) >= 0) {
870 		off_t pos, ret;
871 
872 		pos = (off_t)tty * sizeof(struct utmp);
873 		if ((ret = lseek(fd, pos, SEEK_SET)) == -1) {
874 			logit("%s: lseek: %s", __func__, strerror(errno));
875 			return (0);
876 		}
877 		if (ret != pos) {
878 			logit("%s: Couldn't seek to tty %d slot in %s",
879 			    __func__, tty, UTMP_FILE);
880 			return (0);
881 		}
882 		/*
883 		 * Prevent luser from zero'ing out ut_host.
884 		 * If the new ut_line is empty but the old one is not
885 		 * and ut_line and ut_name match, preserve the old ut_line.
886 		 */
887 		if (atomicio(read, fd, &old_ut, sizeof(old_ut)) == sizeof(old_ut) &&
888 		    (ut->ut_host[0] == '\0') && (old_ut.ut_host[0] != '\0') &&
889 		    (strncmp(old_ut.ut_line, ut->ut_line, sizeof(ut->ut_line)) == 0) &&
890 		    (strncmp(old_ut.ut_name, ut->ut_name, sizeof(ut->ut_name)) == 0))
891 			memcpy(ut->ut_host, old_ut.ut_host, sizeof(ut->ut_host));
892 
893 		if ((ret = lseek(fd, pos, SEEK_SET)) == -1) {
894 			logit("%s: lseek: %s", __func__, strerror(errno));
895 			return (0);
896 		}
897 		if (ret != pos) {
898 			logit("%s: Couldn't seek to tty %d slot in %s",
899 			    __func__, tty, UTMP_FILE);
900 			return (0);
901 		}
902 		if (atomicio(vwrite, fd, ut, sizeof(*ut)) != sizeof(*ut)) {
903 			logit("%s: error writing %s: %s", __func__,
904 			    UTMP_FILE, strerror(errno));
905 		}
906 
907 		close(fd);
908 		return (1);
909 	} else {
910 		return (0);
911 	}
912 }
913 # endif /* UTMP_USE_LIBRARY */
914 
915 static int
916 utmp_perform_login(struct logininfo *li)
917 {
918 	struct utmp ut;
919 
920 	construct_utmp(li, &ut);
921 # ifdef UTMP_USE_LIBRARY
922 	if (!utmp_write_library(li, &ut)) {
923 		logit("%s: utmp_write_library() failed", __func__);
924 		return (0);
925 	}
926 # else
927 	if (!utmp_write_direct(li, &ut)) {
928 		logit("%s: utmp_write_direct() failed", __func__);
929 		return (0);
930 	}
931 # endif
932 	return (1);
933 }
934 
935 
936 static int
937 utmp_perform_logout(struct logininfo *li)
938 {
939 	struct utmp ut;
940 
941 	construct_utmp(li, &ut);
942 # ifdef UTMP_USE_LIBRARY
943 	if (!utmp_write_library(li, &ut)) {
944 		logit("%s: utmp_write_library() failed", __func__);
945 		return (0);
946 	}
947 # else
948 	if (!utmp_write_direct(li, &ut)) {
949 		logit("%s: utmp_write_direct() failed", __func__);
950 		return (0);
951 	}
952 # endif
953 	return (1);
954 }
955 
956 
957 int
958 utmp_write_entry(struct logininfo *li)
959 {
960 	switch(li->type) {
961 	case LTYPE_LOGIN:
962 		return (utmp_perform_login(li));
963 
964 	case LTYPE_LOGOUT:
965 		return (utmp_perform_logout(li));
966 
967 	default:
968 		logit("%s: invalid type field", __func__);
969 		return (0);
970 	}
971 }
972 #endif /* USE_UTMP */
973 
974 
975 /**
976  ** Low-level utmpx functions
977  **/
978 
979 /* not much point if we don't want utmpx entries */
980 #ifdef USE_UTMPX
981 
982 /* if we have the wherewithall, use pututxline etc. */
983 # if !defined(DISABLE_PUTUTXLINE) && defined(HAVE_SETUTXENT) && \
984 	defined(HAVE_PUTUTXLINE)
985 #  define UTMPX_USE_LIBRARY
986 # endif
987 
988 
989 /* write a utmpx entry with the system's help (pututxline() and pals) */
990 # ifdef UTMPX_USE_LIBRARY
991 static int
992 utmpx_write_library(struct logininfo *li, struct utmpx *utx)
993 {
994 	setutxent();
995 	pututxline(utx);
996 
997 #  ifdef HAVE_ENDUTXENT
998 	endutxent();
999 #  endif
1000 	return (1);
1001 }
1002 
1003 # else /* UTMPX_USE_LIBRARY */
1004 
1005 /* write a utmp entry direct to the file */
1006 static int
1007 utmpx_write_direct(struct logininfo *li, struct utmpx *utx)
1008 {
1009 	logit("%s: not implemented!", __func__);
1010 	return (0);
1011 }
1012 # endif /* UTMPX_USE_LIBRARY */
1013 
1014 static int
1015 utmpx_perform_login(struct logininfo *li)
1016 {
1017 	struct utmpx utx;
1018 
1019 	construct_utmpx(li, &utx);
1020 # ifdef UTMPX_USE_LIBRARY
1021 	if (!utmpx_write_library(li, &utx)) {
1022 		logit("%s: utmp_write_library() failed", __func__);
1023 		return (0);
1024 	}
1025 # else
1026 	if (!utmpx_write_direct(li, &ut)) {
1027 		logit("%s: utmp_write_direct() failed", __func__);
1028 		return (0);
1029 	}
1030 # endif
1031 	return (1);
1032 }
1033 
1034 
1035 static int
1036 utmpx_perform_logout(struct logininfo *li)
1037 {
1038 	struct utmpx utx;
1039 
1040 	construct_utmpx(li, &utx);
1041 # ifdef HAVE_ID_IN_UTMPX
1042 	line_abbrevname(utx.ut_id, li->line, sizeof(utx.ut_id));
1043 # endif
1044 # ifdef HAVE_TYPE_IN_UTMPX
1045 	utx.ut_type = DEAD_PROCESS;
1046 # endif
1047 
1048 # ifdef UTMPX_USE_LIBRARY
1049 	utmpx_write_library(li, &utx);
1050 # else
1051 	utmpx_write_direct(li, &utx);
1052 # endif
1053 	return (1);
1054 }
1055 
1056 int
1057 utmpx_write_entry(struct logininfo *li)
1058 {
1059 	switch(li->type) {
1060 	case LTYPE_LOGIN:
1061 		return (utmpx_perform_login(li));
1062 	case LTYPE_LOGOUT:
1063 		return (utmpx_perform_logout(li));
1064 	default:
1065 		logit("%s: invalid type field", __func__);
1066 		return (0);
1067 	}
1068 }
1069 #endif /* USE_UTMPX */
1070 
1071 
1072 /**
1073  ** Low-level wtmp functions
1074  **/
1075 
1076 #ifdef USE_WTMP
1077 
1078 /*
1079  * Write a wtmp entry direct to the end of the file
1080  * This is a slight modification of code in OpenBSD's logwtmp.c
1081  */
1082 static int
1083 wtmp_write(struct logininfo *li, struct utmp *ut)
1084 {
1085 	struct stat buf;
1086 	int fd, ret = 1;
1087 
1088 	if ((fd = open(WTMP_FILE, O_WRONLY|O_APPEND, 0)) < 0) {
1089 		logit("%s: problem writing %s: %s", __func__,
1090 		    WTMP_FILE, strerror(errno));
1091 		return (0);
1092 	}
1093 	if (fstat(fd, &buf) == 0)
1094 		if (atomicio(vwrite, fd, ut, sizeof(*ut)) != sizeof(*ut)) {
1095 			ftruncate(fd, buf.st_size);
1096 			logit("%s: problem writing %s: %s", __func__,
1097 			    WTMP_FILE, strerror(errno));
1098 			ret = 0;
1099 		}
1100 	close(fd);
1101 	return (ret);
1102 }
1103 
1104 static int
1105 wtmp_perform_login(struct logininfo *li)
1106 {
1107 	struct utmp ut;
1108 
1109 	construct_utmp(li, &ut);
1110 	return (wtmp_write(li, &ut));
1111 }
1112 
1113 
1114 static int
1115 wtmp_perform_logout(struct logininfo *li)
1116 {
1117 	struct utmp ut;
1118 
1119 	construct_utmp(li, &ut);
1120 	return (wtmp_write(li, &ut));
1121 }
1122 
1123 
1124 int
1125 wtmp_write_entry(struct logininfo *li)
1126 {
1127 	switch(li->type) {
1128 	case LTYPE_LOGIN:
1129 		return (wtmp_perform_login(li));
1130 	case LTYPE_LOGOUT:
1131 		return (wtmp_perform_logout(li));
1132 	default:
1133 		logit("%s: invalid type field", __func__);
1134 		return (0);
1135 	}
1136 }
1137 
1138 
1139 /*
1140  * Notes on fetching login data from wtmp/wtmpx
1141  *
1142  * Logouts are usually recorded with (amongst other things) a blank
1143  * username on a given tty line.  However, some systems (HP-UX is one)
1144  * leave all fields set, but change the ut_type field to DEAD_PROCESS.
1145  *
1146  * Since we're only looking for logins here, we know that the username
1147  * must be set correctly. On systems that leave it in, we check for
1148  * ut_type==USER_PROCESS (indicating a login.)
1149  *
1150  * Portability: Some systems may set something other than USER_PROCESS
1151  * to indicate a login process. I don't know of any as I write. Also,
1152  * it's possible that some systems may both leave the username in
1153  * place and not have ut_type.
1154  */
1155 
1156 /* return true if this wtmp entry indicates a login */
1157 static int
1158 wtmp_islogin(struct logininfo *li, struct utmp *ut)
1159 {
1160 	if (strncmp(li->username, ut->ut_name,
1161 	    MIN_SIZEOF(li->username, ut->ut_name)) == 0) {
1162 # ifdef HAVE_TYPE_IN_UTMP
1163 		if (ut->ut_type & USER_PROCESS)
1164 			return (1);
1165 # else
1166 		return (1);
1167 # endif
1168 	}
1169 	return (0);
1170 }
1171 
1172 int
1173 wtmp_get_entry(struct logininfo *li)
1174 {
1175 	struct stat st;
1176 	struct utmp ut;
1177 	int fd, found = 0;
1178 
1179 	/* Clear the time entries in our logininfo */
1180 	li->tv_sec = li->tv_usec = 0;
1181 
1182 	if ((fd = open(WTMP_FILE, O_RDONLY)) < 0) {
1183 		logit("%s: problem opening %s: %s", __func__,
1184 		    WTMP_FILE, strerror(errno));
1185 		return (0);
1186 	}
1187 	if (fstat(fd, &st) != 0) {
1188 		logit("%s: couldn't stat %s: %s", __func__,
1189 		    WTMP_FILE, strerror(errno));
1190 		close(fd);
1191 		return (0);
1192 	}
1193 
1194 	/* Seek to the start of the last struct utmp */
1195 	if (lseek(fd, -(off_t)sizeof(struct utmp), SEEK_END) == -1) {
1196 		/* Looks like we've got a fresh wtmp file */
1197 		close(fd);
1198 		return (0);
1199 	}
1200 
1201 	while (!found) {
1202 		if (atomicio(read, fd, &ut, sizeof(ut)) != sizeof(ut)) {
1203 			logit("%s: read of %s failed: %s", __func__,
1204 			    WTMP_FILE, strerror(errno));
1205 			close (fd);
1206 			return (0);
1207 		}
1208 		if ( wtmp_islogin(li, &ut) ) {
1209 			found = 1;
1210 			/*
1211 			 * We've already checked for a time in struct
1212 			 * utmp, in login_getlast()
1213 			 */
1214 # ifdef HAVE_TIME_IN_UTMP
1215 			li->tv_sec = ut.ut_time;
1216 # else
1217 #  if HAVE_TV_IN_UTMP
1218 			li->tv_sec = ut.ut_tv.tv_sec;
1219 #  endif
1220 # endif
1221 			line_fullname(li->line, ut.ut_line,
1222 			    MIN_SIZEOF(li->line, ut.ut_line));
1223 # ifdef HAVE_HOST_IN_UTMP
1224 			strlcpy(li->hostname, ut.ut_host,
1225 			    MIN_SIZEOF(li->hostname, ut.ut_host));
1226 # endif
1227 			continue;
1228 		}
1229 		/* Seek back 2 x struct utmp */
1230 		if (lseek(fd, -(off_t)(2 * sizeof(struct utmp)), SEEK_CUR) == -1) {
1231 			/* We've found the start of the file, so quit */
1232 			close(fd);
1233 			return (0);
1234 		}
1235 	}
1236 
1237 	/* We found an entry. Tidy up and return */
1238 	close(fd);
1239 	return (1);
1240 }
1241 # endif /* USE_WTMP */
1242 
1243 
1244 /**
1245  ** Low-level wtmpx functions
1246  **/
1247 
1248 #ifdef USE_WTMPX
1249 /*
1250  * Write a wtmpx entry direct to the end of the file
1251  * This is a slight modification of code in OpenBSD's logwtmp.c
1252  */
1253 static int
1254 wtmpx_write(struct logininfo *li, struct utmpx *utx)
1255 {
1256 #ifndef HAVE_UPDWTMPX
1257 	struct stat buf;
1258 	int fd, ret = 1;
1259 
1260 	if ((fd = open(WTMPX_FILE, O_WRONLY|O_APPEND, 0)) < 0) {
1261 		logit("%s: problem opening %s: %s", __func__,
1262 		    WTMPX_FILE, strerror(errno));
1263 		return (0);
1264 	}
1265 
1266 	if (fstat(fd, &buf) == 0)
1267 		if (atomicio(vwrite, fd, utx, sizeof(*utx)) != sizeof(*utx)) {
1268 			ftruncate(fd, buf.st_size);
1269 			logit("%s: problem writing %s: %s", __func__,
1270 			    WTMPX_FILE, strerror(errno));
1271 			ret = 0;
1272 		}
1273 	close(fd);
1274 
1275 	return (ret);
1276 #else
1277 	updwtmpx(WTMPX_FILE, utx);
1278 	return (1);
1279 #endif
1280 }
1281 
1282 
1283 static int
1284 wtmpx_perform_login(struct logininfo *li)
1285 {
1286 	struct utmpx utx;
1287 
1288 	construct_utmpx(li, &utx);
1289 	return (wtmpx_write(li, &utx));
1290 }
1291 
1292 
1293 static int
1294 wtmpx_perform_logout(struct logininfo *li)
1295 {
1296 	struct utmpx utx;
1297 
1298 	construct_utmpx(li, &utx);
1299 	return (wtmpx_write(li, &utx));
1300 }
1301 
1302 
1303 int
1304 wtmpx_write_entry(struct logininfo *li)
1305 {
1306 	switch(li->type) {
1307 	case LTYPE_LOGIN:
1308 		return (wtmpx_perform_login(li));
1309 	case LTYPE_LOGOUT:
1310 		return (wtmpx_perform_logout(li));
1311 	default:
1312 		logit("%s: invalid type field", __func__);
1313 		return (0);
1314 	}
1315 }
1316 
1317 /* Please see the notes above wtmp_islogin() for information about the
1318    next two functions */
1319 
1320 /* Return true if this wtmpx entry indicates a login */
1321 static int
1322 wtmpx_islogin(struct logininfo *li, struct utmpx *utx)
1323 {
1324 	if (strncmp(li->username, utx->ut_user,
1325 	    MIN_SIZEOF(li->username, utx->ut_user)) == 0 ) {
1326 # ifdef HAVE_TYPE_IN_UTMPX
1327 		if (utx->ut_type == USER_PROCESS)
1328 			return (1);
1329 # else
1330 		return (1);
1331 # endif
1332 	}
1333 	return (0);
1334 }
1335 
1336 
1337 int
1338 wtmpx_get_entry(struct logininfo *li)
1339 {
1340 	struct stat st;
1341 	struct utmpx utx;
1342 	int fd, found=0;
1343 
1344 	/* Clear the time entries */
1345 	li->tv_sec = li->tv_usec = 0;
1346 
1347 	if ((fd = open(WTMPX_FILE, O_RDONLY)) < 0) {
1348 		logit("%s: problem opening %s: %s", __func__,
1349 		    WTMPX_FILE, strerror(errno));
1350 		return (0);
1351 	}
1352 	if (fstat(fd, &st) != 0) {
1353 		logit("%s: couldn't stat %s: %s", __func__,
1354 		    WTMPX_FILE, strerror(errno));
1355 		close(fd);
1356 		return (0);
1357 	}
1358 
1359 	/* Seek to the start of the last struct utmpx */
1360 	if (lseek(fd, -(off_t)sizeof(struct utmpx), SEEK_END) == -1 ) {
1361 		/* probably a newly rotated wtmpx file */
1362 		close(fd);
1363 		return (0);
1364 	}
1365 
1366 	while (!found) {
1367 		if (atomicio(read, fd, &utx, sizeof(utx)) != sizeof(utx)) {
1368 			logit("%s: read of %s failed: %s", __func__,
1369 			    WTMPX_FILE, strerror(errno));
1370 			close (fd);
1371 			return (0);
1372 		}
1373 		/*
1374 		 * Logouts are recorded as a blank username on a particular
1375 		 * line. So, we just need to find the username in struct utmpx
1376 		 */
1377 		if (wtmpx_islogin(li, &utx)) {
1378 			found = 1;
1379 # if defined(HAVE_TV_IN_UTMPX)
1380 			li->tv_sec = utx.ut_tv.tv_sec;
1381 # elif defined(HAVE_TIME_IN_UTMPX)
1382 			li->tv_sec = utx.ut_time;
1383 # endif
1384 			line_fullname(li->line, utx.ut_line, sizeof(li->line));
1385 # if defined(HAVE_HOST_IN_UTMPX)
1386 			strlcpy(li->hostname, utx.ut_host,
1387 			    MIN_SIZEOF(li->hostname, utx.ut_host));
1388 # endif
1389 			continue;
1390 		}
1391 		if (lseek(fd, -(off_t)(2 * sizeof(struct utmpx)), SEEK_CUR) == -1) {
1392 			close(fd);
1393 			return (0);
1394 		}
1395 	}
1396 
1397 	close(fd);
1398 	return (1);
1399 }
1400 #endif /* USE_WTMPX */
1401 
1402 /**
1403  ** Low-level libutil login() functions
1404  **/
1405 
1406 #ifdef USE_LOGIN
1407 static int
1408 syslogin_perform_login(struct logininfo *li)
1409 {
1410 	struct utmp *ut;
1411 
1412 	ut = xmalloc(sizeof(*ut));
1413 	construct_utmp(li, ut);
1414 	login(ut);
1415 	free(ut);
1416 
1417 	return (1);
1418 }
1419 
1420 static int
1421 syslogin_perform_logout(struct logininfo *li)
1422 {
1423 # ifdef HAVE_LOGOUT
1424 	char line[UT_LINESIZE];
1425 
1426 	(void)line_stripname(line, li->line, sizeof(line));
1427 
1428 	if (!logout(line))
1429 		logit("%s: logout() returned an error", __func__);
1430 #  ifdef HAVE_LOGWTMP
1431 	else
1432 		logwtmp(line, "", "");
1433 #  endif
1434 	/* FIXME: (ATL - if the need arises) What to do if we have
1435 	 * login, but no logout?  what if logout but no logwtmp? All
1436 	 * routines are in libutil so they should all be there,
1437 	 * but... */
1438 # endif
1439 	return (1);
1440 }
1441 
1442 int
1443 syslogin_write_entry(struct logininfo *li)
1444 {
1445 	switch (li->type) {
1446 	case LTYPE_LOGIN:
1447 		return (syslogin_perform_login(li));
1448 	case LTYPE_LOGOUT:
1449 		return (syslogin_perform_logout(li));
1450 	default:
1451 		logit("%s: Invalid type field", __func__);
1452 		return (0);
1453 	}
1454 }
1455 #endif /* USE_LOGIN */
1456 
1457 /* end of file log-syslogin.c */
1458 
1459 /**
1460  ** Low-level lastlog functions
1461  **/
1462 
1463 #ifdef USE_LASTLOG
1464 
1465 #if !defined(LASTLOG_WRITE_PUTUTXLINE) || !defined(HAVE_GETLASTLOGXBYNAME)
1466 /* open the file (using filemode) and seek to the login entry */
1467 static int
1468 lastlog_openseek(struct logininfo *li, int *fd, int filemode)
1469 {
1470 	off_t offset;
1471 	char lastlog_file[1024];
1472 	struct stat st;
1473 
1474 	if (stat(LASTLOG_FILE, &st) != 0) {
1475 		logit("%s: Couldn't stat %s: %s", __func__,
1476 		    LASTLOG_FILE, strerror(errno));
1477 		return (0);
1478 	}
1479 	if (S_ISDIR(st.st_mode)) {
1480 		snprintf(lastlog_file, sizeof(lastlog_file), "%s/%s",
1481 		    LASTLOG_FILE, li->username);
1482 	} else if (S_ISREG(st.st_mode)) {
1483 		strlcpy(lastlog_file, LASTLOG_FILE, sizeof(lastlog_file));
1484 	} else {
1485 		logit("%s: %.100s is not a file or directory!", __func__,
1486 		    LASTLOG_FILE);
1487 		return (0);
1488 	}
1489 
1490 	*fd = open(lastlog_file, filemode, 0600);
1491 	if (*fd < 0) {
1492 		debug("%s: Couldn't open %s: %s", __func__,
1493 		    lastlog_file, strerror(errno));
1494 		return (0);
1495 	}
1496 
1497 	if (S_ISREG(st.st_mode)) {
1498 		/* find this uid's offset in the lastlog file */
1499 		offset = (off_t) ((long)li->uid * sizeof(struct lastlog));
1500 
1501 		if (lseek(*fd, offset, SEEK_SET) != offset) {
1502 			logit("%s: %s->lseek(): %s", __func__,
1503 			    lastlog_file, strerror(errno));
1504 			return (0);
1505 		}
1506 	}
1507 
1508 	return (1);
1509 }
1510 #endif /* !LASTLOG_WRITE_PUTUTXLINE || !HAVE_GETLASTLOGXBYNAME */
1511 
1512 #ifdef LASTLOG_WRITE_PUTUTXLINE
1513 int
1514 lastlog_write_entry(struct logininfo *li)
1515 {
1516 	switch(li->type) {
1517 	case LTYPE_LOGIN:
1518 		return 1; /* lastlog written by pututxline */
1519 	default:
1520 		logit("lastlog_write_entry: Invalid type field");
1521 		return 0;
1522 	}
1523 }
1524 #else /* LASTLOG_WRITE_PUTUTXLINE */
1525 int
1526 lastlog_write_entry(struct logininfo *li)
1527 {
1528 	struct lastlog last;
1529 	int fd;
1530 
1531 	switch(li->type) {
1532 	case LTYPE_LOGIN:
1533 		/* create our struct lastlog */
1534 		memset(&last, '\0', sizeof(last));
1535 		line_stripname(last.ll_line, li->line, sizeof(last.ll_line));
1536 		strlcpy(last.ll_host, li->hostname,
1537 		    MIN_SIZEOF(last.ll_host, li->hostname));
1538 		last.ll_time = li->tv_sec;
1539 
1540 		if (!lastlog_openseek(li, &fd, O_RDWR|O_CREAT))
1541 			return (0);
1542 
1543 		/* write the entry */
1544 		if (atomicio(vwrite, fd, &last, sizeof(last)) != sizeof(last)) {
1545 			close(fd);
1546 			logit("%s: Error writing to %s: %s", __func__,
1547 			    LASTLOG_FILE, strerror(errno));
1548 			return (0);
1549 		}
1550 
1551 		close(fd);
1552 		return (1);
1553 	default:
1554 		logit("%s: Invalid type field", __func__);
1555 		return (0);
1556 	}
1557 }
1558 #endif /* LASTLOG_WRITE_PUTUTXLINE */
1559 
1560 #ifdef HAVE_GETLASTLOGXBYNAME
1561 int
1562 lastlog_get_entry(struct logininfo *li)
1563 {
1564 	struct lastlogx l, *ll;
1565 
1566 	if ((ll = getlastlogxbyname(li->username, &l)) == NULL) {
1567 		memset(&l, '\0', sizeof(l));
1568 		ll = &l;
1569 	}
1570 	line_fullname(li->line, ll->ll_line, sizeof(li->line));
1571 	strlcpy(li->hostname, ll->ll_host,
1572 		MIN_SIZEOF(li->hostname, ll->ll_host));
1573 	li->tv_sec = ll->ll_tv.tv_sec;
1574 	li->tv_usec = ll->ll_tv.tv_usec;
1575 	return (1);
1576 }
1577 #else /* HAVE_GETLASTLOGXBYNAME */
1578 int
1579 lastlog_get_entry(struct logininfo *li)
1580 {
1581 	struct lastlog last;
1582 	int fd, ret;
1583 
1584 	if (!lastlog_openseek(li, &fd, O_RDONLY))
1585 		return (0);
1586 
1587 	ret = atomicio(read, fd, &last, sizeof(last));
1588 	close(fd);
1589 
1590 	switch (ret) {
1591 	case 0:
1592 		memset(&last, '\0', sizeof(last));
1593 		/* FALLTHRU */
1594 	case sizeof(last):
1595 		line_fullname(li->line, last.ll_line, sizeof(li->line));
1596 		strlcpy(li->hostname, last.ll_host,
1597 		    MIN_SIZEOF(li->hostname, last.ll_host));
1598 		li->tv_sec = last.ll_time;
1599 		return (1);
1600 	case -1:
1601 		error("%s: Error reading from %s: %s", __func__,
1602 		    LASTLOG_FILE, strerror(errno));
1603 		return (0);
1604 	default:
1605 		error("%s: Error reading from %s: Expecting %d, got %d",
1606 		    __func__, LASTLOG_FILE, (int)sizeof(last), ret);
1607 		return (0);
1608 	}
1609 
1610 	/* NOTREACHED */
1611 	return (0);
1612 }
1613 #endif /* HAVE_GETLASTLOGXBYNAME */
1614 #endif /* USE_LASTLOG */
1615 
1616 #if defined(USE_UTMPX) && defined(HAVE_SETUTXDB) && \
1617     defined(UTXDB_LASTLOGIN) && defined(HAVE_GETUTXUSER)
1618 int
1619 utmpx_get_entry(struct logininfo *li)
1620 {
1621 	struct utmpx *utx;
1622 
1623 	if (setutxdb(UTXDB_LASTLOGIN, NULL) != 0)
1624 		return (0);
1625 	utx = getutxuser(li->username);
1626 	if (utx == NULL) {
1627 		endutxent();
1628 		return (0);
1629 	}
1630 
1631 	line_fullname(li->line, utx->ut_line,
1632 	    MIN_SIZEOF(li->line, utx->ut_line));
1633 	strlcpy(li->hostname, utx->ut_host,
1634 	    MIN_SIZEOF(li->hostname, utx->ut_host));
1635 	li->tv_sec = utx->ut_tv.tv_sec;
1636 	li->tv_usec = utx->ut_tv.tv_usec;
1637 	endutxent();
1638 	return (1);
1639 }
1640 #endif /* USE_UTMPX && HAVE_SETUTXDB && UTXDB_LASTLOGIN && HAVE_GETUTXUSER */
1641 
1642 #ifdef USE_BTMP
1643   /*
1644    * Logs failed login attempts in _PATH_BTMP if that exists.
1645    * The most common login failure is to give password instead of username.
1646    * So the _PATH_BTMP file checked for the correct permission, so that
1647    * only root can read it.
1648    */
1649 
1650 void
1651 record_failed_login(const char *username, const char *hostname,
1652     const char *ttyn)
1653 {
1654 	int fd;
1655 	struct utmp ut;
1656 	struct sockaddr_storage from;
1657 	socklen_t fromlen = sizeof(from);
1658 	struct sockaddr_in *a4;
1659 	struct sockaddr_in6 *a6;
1660 	time_t t;
1661 	struct stat fst;
1662 
1663 	if (geteuid() != 0)
1664 		return;
1665 	if ((fd = open(_PATH_BTMP, O_WRONLY | O_APPEND)) < 0) {
1666 		debug("Unable to open the btmp file %s: %s", _PATH_BTMP,
1667 		    strerror(errno));
1668 		return;
1669 	}
1670 	if (fstat(fd, &fst) < 0) {
1671 		logit("%s: fstat of %s failed: %s", __func__, _PATH_BTMP,
1672 		    strerror(errno));
1673 		goto out;
1674 	}
1675 	if((fst.st_mode & (S_IRWXG | S_IRWXO)) || (fst.st_uid != 0)){
1676 		logit("Excess permission or bad ownership on file %s",
1677 		    _PATH_BTMP);
1678 		goto out;
1679 	}
1680 
1681 	memset(&ut, 0, sizeof(ut));
1682 	/* strncpy because we don't necessarily want nul termination */
1683 	strncpy(ut.ut_user, username, sizeof(ut.ut_user));
1684 	strlcpy(ut.ut_line, "ssh:notty", sizeof(ut.ut_line));
1685 
1686 	time(&t);
1687 	ut.ut_time = t;     /* ut_time is not always a time_t */
1688 	ut.ut_type = LOGIN_PROCESS;
1689 	ut.ut_pid = getpid();
1690 
1691 	/* strncpy because we don't necessarily want nul termination */
1692 	strncpy(ut.ut_host, hostname, sizeof(ut.ut_host));
1693 
1694 	if (packet_connection_is_on_socket() &&
1695 	    getpeername(packet_get_connection_in(),
1696 	    (struct sockaddr *)&from, &fromlen) == 0) {
1697 		ipv64_normalise_mapped(&from, &fromlen);
1698 		if (from.ss_family == AF_INET) {
1699 			a4 = (struct sockaddr_in *)&from;
1700 			memcpy(&ut.ut_addr, &(a4->sin_addr),
1701 			    MIN_SIZEOF(ut.ut_addr, a4->sin_addr));
1702 		}
1703 #ifdef HAVE_ADDR_V6_IN_UTMP
1704 		if (from.ss_family == AF_INET6) {
1705 			a6 = (struct sockaddr_in6 *)&from;
1706 			memcpy(&ut.ut_addr_v6, &(a6->sin6_addr),
1707 			    MIN_SIZEOF(ut.ut_addr_v6, a6->sin6_addr));
1708 		}
1709 #endif
1710 	}
1711 
1712 	if (atomicio(vwrite, fd, &ut, sizeof(ut)) != sizeof(ut))
1713 		error("Failed to write to %s: %s", _PATH_BTMP,
1714 		    strerror(errno));
1715 
1716 out:
1717 	close(fd);
1718 }
1719 #endif	/* USE_BTMP */
1720