xref: /dragonfly/crypto/openssh/loginrec.c (revision 2c81fb9c)
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 MERCHANTABILITY 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 #ifdef HAVE_SYS_TIME_H
154 # include <sys/time.h>
155 #endif
156 
157 #include <netinet/in.h>
158 
159 #include <stdlib.h>
160 #include <errno.h>
161 #include <fcntl.h>
162 #ifdef HAVE_PATHS_H
163 # include <paths.h>
164 #endif
165 #include <pwd.h>
166 #include <stdarg.h>
167 #include <stdio.h>
168 #include <string.h>
169 #include <time.h>
170 #include <unistd.h>
171 
172 #include "xmalloc.h"
173 #include "sshkey.h"
174 #include "hostfile.h"
175 #include "ssh.h"
176 #include "loginrec.h"
177 #include "log.h"
178 #include "atomicio.h"
179 #include "packet.h"
180 #include "canohost.h"
181 #include "auth.h"
182 #include "sshbuf.h"
183 #include "ssherr.h"
184 #include "misc.h"
185 
186 #ifdef HAVE_UTIL_H
187 # include <util.h>
188 #endif
189 
190 /**
191  ** prototypes for helper functions in this file
192  **/
193 
194 #ifdef HAVE_UTMP_H
195 void set_utmp_time(struct logininfo *li, struct utmp *ut);
196 void construct_utmp(struct logininfo *li, struct utmp *ut);
197 #endif
198 
199 #ifdef HAVE_UTMPX_H
200 void set_utmpx_time(struct logininfo *li, struct utmpx *ut);
201 void construct_utmpx(struct logininfo *li, struct utmpx *ut);
202 #endif
203 
204 int utmp_write_entry(struct logininfo *li);
205 int utmpx_write_entry(struct logininfo *li);
206 int wtmp_write_entry(struct logininfo *li);
207 int wtmpx_write_entry(struct logininfo *li);
208 int lastlog_write_entry(struct logininfo *li);
209 int syslogin_write_entry(struct logininfo *li);
210 
211 int getlast_entry(struct logininfo *li);
212 int lastlog_get_entry(struct logininfo *li);
213 int utmpx_get_entry(struct logininfo *li);
214 int wtmp_get_entry(struct logininfo *li);
215 int wtmpx_get_entry(struct logininfo *li);
216 
217 extern struct sshbuf *loginmsg;
218 
219 /* pick the shortest string */
220 #define MIN_SIZEOF(s1,s2) (sizeof(s1) < sizeof(s2) ? sizeof(s1) : sizeof(s2))
221 
222 /**
223  ** platform-independent login functions
224  **/
225 
226 /*
227  * login_login(struct logininfo *) - Record a login
228  *
229  * Call with a pointer to a struct logininfo initialised with
230  * login_init_entry() or login_alloc_entry()
231  *
232  * Returns:
233  *  >0 if successful
234  *  0  on failure (will use OpenSSH's logging facilities for diagnostics)
235  */
236 int
237 login_login(struct logininfo *li)
238 {
239 	li->type = LTYPE_LOGIN;
240 	return (login_write(li));
241 }
242 
243 
244 /*
245  * login_logout(struct logininfo *) - Record a logout
246  *
247  * Call as with login_login()
248  *
249  * Returns:
250  *  >0 if successful
251  *  0  on failure (will use OpenSSH's logging facilities for diagnostics)
252  */
253 int
254 login_logout(struct logininfo *li)
255 {
256 	li->type = LTYPE_LOGOUT;
257 	return (login_write(li));
258 }
259 
260 /*
261  * login_get_lastlog_time(int) - Retrieve the last login time
262  *
263  * Retrieve the last login time for the given uid. Will try to use the
264  * system lastlog facilities if they are available, but will fall back
265  * to looking in wtmp/wtmpx if necessary
266  *
267  * Returns:
268  *   0 on failure, or if user has never logged in
269  *   Time in seconds from the epoch if successful
270  *
271  * Useful preprocessor symbols:
272  *   DISABLE_LASTLOG: If set, *never* even try to retrieve lastlog
273  *                    info
274  *   USE_LASTLOG: If set, indicates the presence of system lastlog
275  *                facilities. If this and DISABLE_LASTLOG are not set,
276  *                try to retrieve lastlog information from wtmp/wtmpx.
277  */
278 unsigned int
279 login_get_lastlog_time(const uid_t uid)
280 {
281 	struct logininfo li;
282 
283 	if (login_get_lastlog(&li, uid))
284 		return (li.tv_sec);
285 	else
286 		return (0);
287 }
288 
289 /*
290  * login_get_lastlog(struct logininfo *, int)   - Retrieve a lastlog entry
291  *
292  * Retrieve a logininfo structure populated (only partially) with
293  * information from the system lastlog data, or from wtmp/wtmpx if no
294  * system lastlog information exists.
295  *
296  * Note this routine must be given a pre-allocated logininfo.
297  *
298  * Returns:
299  *  >0: A pointer to your struct logininfo if successful
300  *  0  on failure (will use OpenSSH's logging facilities for diagnostics)
301  */
302 struct logininfo *
303 login_get_lastlog(struct logininfo *li, const uid_t uid)
304 {
305 	struct passwd *pw;
306 
307 	memset(li, '\0', sizeof(*li));
308 	li->uid = uid;
309 
310 	/*
311 	 * If we don't have a 'real' lastlog, we need the username to
312 	 * reliably search wtmp(x) for the last login (see
313 	 * wtmp_get_entry().)
314 	 */
315 	pw = getpwuid(uid);
316 	if (pw == NULL)
317 		fatal("%s: Cannot find account for uid %ld", __func__,
318 		    (long)uid);
319 
320 	if (strlcpy(li->username, pw->pw_name, sizeof(li->username)) >=
321 	    sizeof(li->username)) {
322 		error("%s: username too long (%lu > max %lu)", __func__,
323 		    (unsigned long)strlen(pw->pw_name),
324 		    (unsigned long)sizeof(li->username) - 1);
325 		return NULL;
326 	}
327 
328 	if (getlast_entry(li))
329 		return (li);
330 	else
331 		return (NULL);
332 }
333 
334 /*
335  * login_alloc_entry(int, char*, char*, char*)    - Allocate and initialise
336  *                                                  a logininfo structure
337  *
338  * This function creates a new struct logininfo, a data structure
339  * meant to carry the information required to portably record login info.
340  *
341  * Returns a pointer to a newly created struct logininfo. If memory
342  * allocation fails, the program halts.
343  */
344 struct
345 logininfo *login_alloc_entry(pid_t pid, const char *username,
346     const char *hostname, const char *line)
347 {
348 	struct logininfo *newli;
349 
350 	newli = xmalloc(sizeof(*newli));
351 	login_init_entry(newli, pid, username, hostname, line);
352 	return (newli);
353 }
354 
355 
356 /* login_free_entry(struct logininfo *)    - free struct memory */
357 void
358 login_free_entry(struct logininfo *li)
359 {
360 	free(li);
361 }
362 
363 
364 /* login_init_entry(struct logininfo *, int, char*, char*, char*)
365  *                                        - initialise a struct logininfo
366  *
367  * Populates a new struct logininfo, a data structure meant to carry
368  * the information required to portably record login info.
369  *
370  * Returns: 1
371  */
372 int
373 login_init_entry(struct logininfo *li, pid_t pid, const char *username,
374     const char *hostname, const char *line)
375 {
376 	struct passwd *pw;
377 
378 	memset(li, 0, sizeof(*li));
379 
380 	li->pid = pid;
381 
382 	/* set the line information */
383 	if (line)
384 		line_fullname(li->line, line, sizeof(li->line));
385 
386 	if (username) {
387 		strlcpy(li->username, username, sizeof(li->username));
388 		pw = getpwnam(li->username);
389 		if (pw == NULL) {
390 			fatal("%s: Cannot find user \"%s\"", __func__,
391 			    li->username);
392 		}
393 		li->uid = pw->pw_uid;
394 	}
395 
396 	if (hostname)
397 		strlcpy(li->hostname, hostname, sizeof(li->hostname));
398 
399 	return (1);
400 }
401 
402 /*
403  * login_set_current_time(struct logininfo *)    - set the current time
404  *
405  * Set the current time in a logininfo structure. This function is
406  * meant to eliminate the need to deal with system dependencies for
407  * time handling.
408  */
409 void
410 login_set_current_time(struct logininfo *li)
411 {
412 	struct timeval tv;
413 
414 	gettimeofday(&tv, NULL);
415 
416 	li->tv_sec = tv.tv_sec;
417 	li->tv_usec = tv.tv_usec;
418 }
419 
420 /* copy a sockaddr_* into our logininfo */
421 void
422 login_set_addr(struct logininfo *li, const struct sockaddr *sa,
423     const unsigned int sa_size)
424 {
425 	unsigned int bufsize = sa_size;
426 
427 	/* make sure we don't overrun our union */
428 	if (sizeof(li->hostaddr) < sa_size)
429 		bufsize = sizeof(li->hostaddr);
430 
431 	memcpy(&li->hostaddr.sa, sa, bufsize);
432 }
433 
434 
435 /**
436  ** login_write: Call low-level recording functions based on autoconf
437  ** results
438  **/
439 int
440 login_write(struct logininfo *li)
441 {
442 #ifndef HAVE_CYGWIN
443 	if (geteuid() != 0) {
444 		logit("Attempt to write login records by non-root user (aborting)");
445 		return (1);
446 	}
447 #endif
448 
449 	/* set the timestamp */
450 	login_set_current_time(li);
451 #ifdef USE_LOGIN
452 	syslogin_write_entry(li);
453 #endif
454 #ifdef USE_LASTLOG
455 	if (li->type == LTYPE_LOGIN)
456 		lastlog_write_entry(li);
457 #endif
458 #ifdef USE_UTMP
459 	utmp_write_entry(li);
460 #endif
461 #ifdef USE_WTMP
462 	wtmp_write_entry(li);
463 #endif
464 #ifdef USE_UTMPX
465 	utmpx_write_entry(li);
466 #endif
467 #ifdef USE_WTMPX
468 	wtmpx_write_entry(li);
469 #endif
470 #ifdef CUSTOM_SYS_AUTH_RECORD_LOGIN
471 	if (li->type == LTYPE_LOGIN &&
472 	    !sys_auth_record_login(li->username,li->hostname,li->line,
473 	    loginmsg))
474 		logit("Writing login record failed for %s", li->username);
475 #endif
476 #ifdef SSH_AUDIT_EVENTS
477 	if (li->type == LTYPE_LOGIN)
478 		audit_session_open(li);
479 	else if (li->type == LTYPE_LOGOUT)
480 		audit_session_close(li);
481 #endif
482 	return (0);
483 }
484 
485 #ifdef LOGIN_NEEDS_UTMPX
486 int
487 login_utmp_only(struct logininfo *li)
488 {
489 	li->type = LTYPE_LOGIN;
490 	login_set_current_time(li);
491 # ifdef USE_UTMP
492 	utmp_write_entry(li);
493 # endif
494 # ifdef USE_WTMP
495 	wtmp_write_entry(li);
496 # endif
497 # ifdef USE_UTMPX
498 	utmpx_write_entry(li);
499 # endif
500 # ifdef USE_WTMPX
501 	wtmpx_write_entry(li);
502 # endif
503 	return (0);
504 }
505 #endif
506 
507 /**
508  ** getlast_entry: Call low-level functions to retrieve the last login
509  **                time.
510  **/
511 
512 /* take the uid in li and return the last login time */
513 int
514 getlast_entry(struct logininfo *li)
515 {
516 #ifdef USE_LASTLOG
517 	return(lastlog_get_entry(li));
518 #else /* !USE_LASTLOG */
519 #if defined(USE_UTMPX) && defined(HAVE_SETUTXDB) && \
520     defined(UTXDB_LASTLOGIN) && defined(HAVE_GETUTXUSER)
521 	return (utmpx_get_entry(li));
522 #endif
523 
524 #if defined(DISABLE_LASTLOG)
525 	/* On some systems we shouldn't even try to obtain last login
526 	 * time, e.g. AIX */
527 	return (0);
528 # elif defined(USE_WTMP) && \
529     (defined(HAVE_TIME_IN_UTMP) || defined(HAVE_TV_IN_UTMP))
530 	/* retrieve last login time from utmp */
531 	return (wtmp_get_entry(li));
532 # elif defined(USE_WTMPX) && \
533     (defined(HAVE_TIME_IN_UTMPX) || defined(HAVE_TV_IN_UTMPX))
534 	/* If wtmp isn't available, try wtmpx */
535 	return (wtmpx_get_entry(li));
536 # else
537 	/* Give up: No means of retrieving last login time */
538 	return (0);
539 # endif /* DISABLE_LASTLOG */
540 #endif /* USE_LASTLOG */
541 }
542 
543 
544 
545 /*
546  * 'line' string utility functions
547  *
548  * These functions process the 'line' string into one of three forms:
549  *
550  * 1. The full filename (including '/dev')
551  * 2. The stripped name (excluding '/dev')
552  * 3. The abbreviated name (e.g. /dev/ttyp00 -> yp00
553  *                               /dev/pts/1  -> ts/1 )
554  *
555  * Form 3 is used on some systems to identify a .tmp.? entry when
556  * attempting to remove it. Typically both addition and removal is
557  * performed by one application - say, sshd - so as long as the choice
558  * uniquely identifies a terminal it's ok.
559  */
560 
561 
562 /*
563  * line_fullname(): add the leading '/dev/' if it doesn't exist make
564  * sure dst has enough space, if not just copy src (ugh)
565  */
566 char *
567 line_fullname(char *dst, const char *src, u_int dstsize)
568 {
569 	memset(dst, '\0', dstsize);
570 	if ((strncmp(src, "/dev/", 5) == 0) || (dstsize < (strlen(src) + 5)))
571 		strlcpy(dst, src, dstsize);
572 	else {
573 		strlcpy(dst, "/dev/", dstsize);
574 		strlcat(dst, src, dstsize);
575 	}
576 	return (dst);
577 }
578 
579 /* line_stripname(): strip the leading '/dev' if it exists, return dst */
580 char *
581 line_stripname(char *dst, const char *src, int dstsize)
582 {
583 	memset(dst, '\0', dstsize);
584 	if (strncmp(src, "/dev/", 5) == 0)
585 		strlcpy(dst, src + 5, dstsize);
586 	else
587 		strlcpy(dst, src, dstsize);
588 	return (dst);
589 }
590 
591 /*
592  * line_abbrevname(): Return the abbreviated (usually four-character)
593  * form of the line (Just use the last <dstsize> characters of the
594  * full name.)
595  *
596  * NOTE: use strncpy because we do NOT necessarily want zero
597  * termination
598  */
599 char *
600 line_abbrevname(char *dst, const char *src, int dstsize)
601 {
602 	size_t len;
603 
604 	memset(dst, '\0', dstsize);
605 
606 	/* Always skip prefix if present */
607 	if (strncmp(src, "/dev/", 5) == 0)
608 		src += 5;
609 
610 #ifdef WITH_ABBREV_NO_TTY
611 	if (strncmp(src, "tty", 3) == 0)
612 		src += 3;
613 #endif
614 
615 	len = strlen(src);
616 
617 	if (len > 0) {
618 		if (((int)len - dstsize) > 0)
619 			src +=  ((int)len - dstsize);
620 
621 		/* note: _don't_ change this to strlcpy */
622 		strncpy(dst, src, (size_t)dstsize);
623 	}
624 
625 	return (dst);
626 }
627 
628 /**
629  ** utmp utility functions
630  **
631  ** These functions manipulate struct utmp, taking system differences
632  ** into account.
633  **/
634 
635 #if defined(USE_UTMP) || defined (USE_WTMP) || defined (USE_LOGIN)
636 
637 /* build the utmp structure */
638 void
639 set_utmp_time(struct logininfo *li, struct utmp *ut)
640 {
641 # if defined(HAVE_TV_IN_UTMP)
642 	ut->ut_tv.tv_sec = li->tv_sec;
643 	ut->ut_tv.tv_usec = li->tv_usec;
644 # elif defined(HAVE_TIME_IN_UTMP)
645 	ut->ut_time = li->tv_sec;
646 # endif
647 }
648 
649 void
650 construct_utmp(struct logininfo *li,
651 		    struct utmp *ut)
652 {
653 # ifdef HAVE_ADDR_V6_IN_UTMP
654 	struct sockaddr_in6 *sa6;
655 # endif
656 
657 	memset(ut, '\0', sizeof(*ut));
658 
659 	/* First fill out fields used for both logins and logouts */
660 
661 # ifdef HAVE_ID_IN_UTMP
662 	line_abbrevname(ut->ut_id, li->line, sizeof(ut->ut_id));
663 # endif
664 
665 # ifdef HAVE_TYPE_IN_UTMP
666 	/* This is done here to keep utmp constants out of struct logininfo */
667 	switch (li->type) {
668 	case LTYPE_LOGIN:
669 		ut->ut_type = USER_PROCESS;
670 		break;
671 	case LTYPE_LOGOUT:
672 		ut->ut_type = DEAD_PROCESS;
673 		break;
674 	}
675 # endif
676 	set_utmp_time(li, ut);
677 
678 	line_stripname(ut->ut_line, li->line, sizeof(ut->ut_line));
679 
680 # ifdef HAVE_PID_IN_UTMP
681 	ut->ut_pid = li->pid;
682 # endif
683 
684 	/* If we're logging out, leave all other fields blank */
685 	if (li->type == LTYPE_LOGOUT)
686 		return;
687 
688 	/*
689 	 * These fields are only used when logging in, and are blank
690 	 * for logouts.
691 	 */
692 
693 	/* Use strncpy because we don't necessarily want null termination */
694 	strncpy(ut->ut_name, li->username,
695 	    MIN_SIZEOF(ut->ut_name, li->username));
696 # ifdef HAVE_HOST_IN_UTMP
697 	strncpy(ut->ut_host, li->hostname,
698 	    MIN_SIZEOF(ut->ut_host, li->hostname));
699 # endif
700 # ifdef HAVE_ADDR_IN_UTMP
701 	/* this is just a 32-bit IP address */
702 	if (li->hostaddr.sa.sa_family == AF_INET)
703 		ut->ut_addr = li->hostaddr.sa_in.sin_addr.s_addr;
704 # endif
705 # ifdef HAVE_ADDR_V6_IN_UTMP
706 	/* this is just a 128-bit IPv6 address */
707 	if (li->hostaddr.sa.sa_family == AF_INET6) {
708 		sa6 = ((struct sockaddr_in6 *)&li->hostaddr.sa);
709 		memcpy(ut->ut_addr_v6, sa6->sin6_addr.s6_addr, 16);
710 		if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr)) {
711 			ut->ut_addr_v6[0] = ut->ut_addr_v6[3];
712 			ut->ut_addr_v6[1] = 0;
713 			ut->ut_addr_v6[2] = 0;
714 			ut->ut_addr_v6[3] = 0;
715 		}
716 	}
717 # endif
718 }
719 #endif /* USE_UTMP || USE_WTMP || USE_LOGIN */
720 
721 /**
722  ** utmpx utility functions
723  **
724  ** These functions manipulate struct utmpx, accounting for system
725  ** variations.
726  **/
727 
728 #if defined(USE_UTMPX) || defined (USE_WTMPX)
729 /* build the utmpx structure */
730 void
731 set_utmpx_time(struct logininfo *li, struct utmpx *utx)
732 {
733 # if defined(HAVE_TV_IN_UTMPX)
734 	utx->ut_tv.tv_sec = li->tv_sec;
735 	utx->ut_tv.tv_usec = li->tv_usec;
736 # elif defined(HAVE_TIME_IN_UTMPX)
737 	utx->ut_time = li->tv_sec;
738 # endif
739 }
740 
741 void
742 construct_utmpx(struct logininfo *li, struct utmpx *utx)
743 {
744 # ifdef HAVE_ADDR_V6_IN_UTMP
745 	struct sockaddr_in6 *sa6;
746 #  endif
747 	memset(utx, '\0', sizeof(*utx));
748 
749 # ifdef HAVE_ID_IN_UTMPX
750 	line_abbrevname(utx->ut_id, li->line, sizeof(utx->ut_id));
751 # endif
752 
753 	/* this is done here to keep utmp constants out of loginrec.h */
754 	switch (li->type) {
755 	case LTYPE_LOGIN:
756 		utx->ut_type = USER_PROCESS;
757 		break;
758 	case LTYPE_LOGOUT:
759 		utx->ut_type = DEAD_PROCESS;
760 		break;
761 	}
762 	line_stripname(utx->ut_line, li->line, sizeof(utx->ut_line));
763 	set_utmpx_time(li, utx);
764 	utx->ut_pid = li->pid;
765 
766 	/* strncpy(): Don't necessarily want null termination */
767 	strncpy(utx->ut_user, li->username,
768 	    MIN_SIZEOF(utx->ut_user, li->username));
769 
770 	if (li->type == LTYPE_LOGOUT)
771 		return;
772 
773 	/*
774 	 * These fields are only used when logging in, and are blank
775 	 * for logouts.
776 	 */
777 
778 # ifdef HAVE_HOST_IN_UTMPX
779 	strncpy(utx->ut_host, li->hostname,
780 	    MIN_SIZEOF(utx->ut_host, li->hostname));
781 # endif
782 # ifdef HAVE_SS_IN_UTMPX
783 	utx->ut_ss = li->hostaddr.sa_storage;
784 # endif
785 # ifdef HAVE_ADDR_IN_UTMPX
786 	/* this is just a 32-bit IP address */
787 	if (li->hostaddr.sa.sa_family == AF_INET)
788 		utx->ut_addr = li->hostaddr.sa_in.sin_addr.s_addr;
789 # endif
790 # ifdef HAVE_ADDR_V6_IN_UTMP
791 	/* this is just a 128-bit IPv6 address */
792 	if (li->hostaddr.sa.sa_family == AF_INET6) {
793 		sa6 = ((struct sockaddr_in6 *)&li->hostaddr.sa);
794 		memcpy(utx->ut_addr_v6, sa6->sin6_addr.s6_addr, 16);
795 		if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr)) {
796 			utx->ut_addr_v6[0] = utx->ut_addr_v6[3];
797 			utx->ut_addr_v6[1] = 0;
798 			utx->ut_addr_v6[2] = 0;
799 			utx->ut_addr_v6[3] = 0;
800 		}
801 	}
802 # endif
803 # ifdef HAVE_SYSLEN_IN_UTMPX
804 	/* ut_syslen is the length of the utx_host string */
805 	utx->ut_syslen = MINIMUM(strlen(li->hostname), sizeof(utx->ut_host));
806 # endif
807 }
808 #endif /* USE_UTMPX || USE_WTMPX */
809 
810 /**
811  ** Low-level utmp functions
812  **/
813 
814 /* FIXME: (ATL) utmp_write_direct needs testing */
815 #ifdef USE_UTMP
816 
817 /* if we can, use pututline() etc. */
818 # if !defined(DISABLE_PUTUTLINE) && defined(HAVE_SETUTENT) && \
819 	defined(HAVE_PUTUTLINE)
820 #  define UTMP_USE_LIBRARY
821 # endif
822 
823 
824 /* write a utmp entry with the system's help (pututline() and pals) */
825 # ifdef UTMP_USE_LIBRARY
826 static int
827 utmp_write_library(struct logininfo *li, struct utmp *ut)
828 {
829 	setutent();
830 	pututline(ut);
831 #  ifdef HAVE_ENDUTENT
832 	endutent();
833 #  endif
834 	return (1);
835 }
836 # else /* UTMP_USE_LIBRARY */
837 
838 /*
839  * Write a utmp entry direct to the file
840  * This is a slightly modification of code in OpenBSD's login.c
841  */
842 static int
843 utmp_write_direct(struct logininfo *li, struct utmp *ut)
844 {
845 	struct utmp old_ut;
846 	register int fd;
847 	int tty;
848 
849 	/* FIXME: (ATL) ttyslot() needs local implementation */
850 
851 #if defined(HAVE_GETTTYENT)
852 	struct ttyent *ty;
853 
854 	tty=0;
855 	setttyent();
856 	while (NULL != (ty = getttyent())) {
857 		tty++;
858 		if (!strncmp(ty->ty_name, ut->ut_line, sizeof(ut->ut_line)))
859 			break;
860 	}
861 	endttyent();
862 
863 	if (NULL == ty) {
864 		logit("%s: tty not found", __func__);
865 		return (0);
866 	}
867 #else /* FIXME */
868 
869 	tty = ttyslot(); /* seems only to work for /dev/ttyp? style names */
870 
871 #endif /* HAVE_GETTTYENT */
872 
873 	if (tty > 0 && (fd = open(UTMP_FILE, O_RDWR|O_CREAT, 0644)) >= 0) {
874 		off_t pos, ret;
875 
876 		pos = (off_t)tty * sizeof(struct utmp);
877 		if ((ret = lseek(fd, pos, SEEK_SET)) == -1) {
878 			logit("%s: lseek: %s", __func__, strerror(errno));
879 			close(fd);
880 			return (0);
881 		}
882 		if (ret != pos) {
883 			logit("%s: Couldn't seek to tty %d slot in %s",
884 			    __func__, tty, UTMP_FILE);
885 			close(fd);
886 			return (0);
887 		}
888 		/*
889 		 * Prevent luser from zero'ing out ut_host.
890 		 * If the new ut_line is empty but the old one is not
891 		 * and ut_line and ut_name match, preserve the old ut_line.
892 		 */
893 		if (atomicio(read, fd, &old_ut, sizeof(old_ut)) == sizeof(old_ut) &&
894 		    (ut->ut_host[0] == '\0') && (old_ut.ut_host[0] != '\0') &&
895 		    (strncmp(old_ut.ut_line, ut->ut_line, sizeof(ut->ut_line)) == 0) &&
896 		    (strncmp(old_ut.ut_name, ut->ut_name, sizeof(ut->ut_name)) == 0))
897 			memcpy(ut->ut_host, old_ut.ut_host, sizeof(ut->ut_host));
898 
899 		if ((ret = lseek(fd, pos, SEEK_SET)) == -1) {
900 			logit("%s: lseek: %s", __func__, strerror(errno));
901 			close(fd);
902 			return (0);
903 		}
904 		if (ret != pos) {
905 			logit("%s: Couldn't seek to tty %d slot in %s",
906 			    __func__, tty, UTMP_FILE);
907 			close(fd);
908 			return (0);
909 		}
910 		if (atomicio(vwrite, fd, ut, sizeof(*ut)) != sizeof(*ut)) {
911 			logit("%s: error writing %s: %s", __func__,
912 			    UTMP_FILE, strerror(errno));
913 			close(fd);
914 			return (0);
915 		}
916 
917 		close(fd);
918 		return (1);
919 	} else {
920 		return (0);
921 	}
922 }
923 # endif /* UTMP_USE_LIBRARY */
924 
925 static int
926 utmp_perform_login(struct logininfo *li)
927 {
928 	struct utmp ut;
929 
930 	construct_utmp(li, &ut);
931 # ifdef UTMP_USE_LIBRARY
932 	if (!utmp_write_library(li, &ut)) {
933 		logit("%s: utmp_write_library() failed", __func__);
934 		return (0);
935 	}
936 # else
937 	if (!utmp_write_direct(li, &ut)) {
938 		logit("%s: utmp_write_direct() failed", __func__);
939 		return (0);
940 	}
941 # endif
942 	return (1);
943 }
944 
945 
946 static int
947 utmp_perform_logout(struct logininfo *li)
948 {
949 	struct utmp ut;
950 
951 	construct_utmp(li, &ut);
952 # ifdef UTMP_USE_LIBRARY
953 	if (!utmp_write_library(li, &ut)) {
954 		logit("%s: utmp_write_library() failed", __func__);
955 		return (0);
956 	}
957 # else
958 	if (!utmp_write_direct(li, &ut)) {
959 		logit("%s: utmp_write_direct() failed", __func__);
960 		return (0);
961 	}
962 # endif
963 	return (1);
964 }
965 
966 
967 int
968 utmp_write_entry(struct logininfo *li)
969 {
970 	switch(li->type) {
971 	case LTYPE_LOGIN:
972 		return (utmp_perform_login(li));
973 
974 	case LTYPE_LOGOUT:
975 		return (utmp_perform_logout(li));
976 
977 	default:
978 		logit("%s: invalid type field", __func__);
979 		return (0);
980 	}
981 }
982 #endif /* USE_UTMP */
983 
984 
985 /**
986  ** Low-level utmpx functions
987  **/
988 
989 /* not much point if we don't want utmpx entries */
990 #ifdef USE_UTMPX
991 
992 /* if we have the wherewithall, use pututxline etc. */
993 # if !defined(DISABLE_PUTUTXLINE) && defined(HAVE_SETUTXENT) && \
994 	defined(HAVE_PUTUTXLINE)
995 #  define UTMPX_USE_LIBRARY
996 # endif
997 
998 
999 /* write a utmpx entry with the system's help (pututxline() and pals) */
1000 # ifdef UTMPX_USE_LIBRARY
1001 static int
1002 utmpx_write_library(struct logininfo *li, struct utmpx *utx)
1003 {
1004 	setutxent();
1005 	pututxline(utx);
1006 
1007 #  ifdef HAVE_ENDUTXENT
1008 	endutxent();
1009 #  endif
1010 	return (1);
1011 }
1012 
1013 # else /* UTMPX_USE_LIBRARY */
1014 
1015 /* write a utmp entry direct to the file */
1016 static int
1017 utmpx_write_direct(struct logininfo *li, struct utmpx *utx)
1018 {
1019 	logit("%s: not implemented!", __func__);
1020 	return (0);
1021 }
1022 # endif /* UTMPX_USE_LIBRARY */
1023 
1024 static int
1025 utmpx_perform_login(struct logininfo *li)
1026 {
1027 	struct utmpx utx;
1028 
1029 	construct_utmpx(li, &utx);
1030 # ifdef UTMPX_USE_LIBRARY
1031 	if (!utmpx_write_library(li, &utx)) {
1032 		logit("%s: utmp_write_library() failed", __func__);
1033 		return (0);
1034 	}
1035 # else
1036 	if (!utmpx_write_direct(li, &ut)) {
1037 		logit("%s: utmp_write_direct() failed", __func__);
1038 		return (0);
1039 	}
1040 # endif
1041 	return (1);
1042 }
1043 
1044 
1045 static int
1046 utmpx_perform_logout(struct logininfo *li)
1047 {
1048 	struct utmpx utx;
1049 
1050 	construct_utmpx(li, &utx);
1051 # ifdef HAVE_ID_IN_UTMPX
1052 	line_abbrevname(utx.ut_id, li->line, sizeof(utx.ut_id));
1053 # endif
1054 # ifdef HAVE_TYPE_IN_UTMPX
1055 	utx.ut_type = DEAD_PROCESS;
1056 # endif
1057 
1058 # ifdef UTMPX_USE_LIBRARY
1059 	utmpx_write_library(li, &utx);
1060 # else
1061 	utmpx_write_direct(li, &utx);
1062 # endif
1063 	return (1);
1064 }
1065 
1066 int
1067 utmpx_write_entry(struct logininfo *li)
1068 {
1069 	switch(li->type) {
1070 	case LTYPE_LOGIN:
1071 		return (utmpx_perform_login(li));
1072 	case LTYPE_LOGOUT:
1073 		return (utmpx_perform_logout(li));
1074 	default:
1075 		logit("%s: invalid type field", __func__);
1076 		return (0);
1077 	}
1078 }
1079 #endif /* USE_UTMPX */
1080 
1081 
1082 /**
1083  ** Low-level wtmp functions
1084  **/
1085 
1086 #ifdef USE_WTMP
1087 
1088 /*
1089  * Write a wtmp entry direct to the end of the file
1090  * This is a slight modification of code in OpenBSD's logwtmp.c
1091  */
1092 static int
1093 wtmp_write(struct logininfo *li, struct utmp *ut)
1094 {
1095 	struct stat buf;
1096 	int fd, ret = 1;
1097 
1098 	if ((fd = open(WTMP_FILE, O_WRONLY|O_APPEND, 0)) < 0) {
1099 		logit("%s: problem writing %s: %s", __func__,
1100 		    WTMP_FILE, strerror(errno));
1101 		return (0);
1102 	}
1103 	if (fstat(fd, &buf) == 0)
1104 		if (atomicio(vwrite, fd, ut, sizeof(*ut)) != sizeof(*ut)) {
1105 			ftruncate(fd, buf.st_size);
1106 			logit("%s: problem writing %s: %s", __func__,
1107 			    WTMP_FILE, strerror(errno));
1108 			ret = 0;
1109 		}
1110 	close(fd);
1111 	return (ret);
1112 }
1113 
1114 static int
1115 wtmp_perform_login(struct logininfo *li)
1116 {
1117 	struct utmp ut;
1118 
1119 	construct_utmp(li, &ut);
1120 	return (wtmp_write(li, &ut));
1121 }
1122 
1123 
1124 static int
1125 wtmp_perform_logout(struct logininfo *li)
1126 {
1127 	struct utmp ut;
1128 
1129 	construct_utmp(li, &ut);
1130 	return (wtmp_write(li, &ut));
1131 }
1132 
1133 
1134 int
1135 wtmp_write_entry(struct logininfo *li)
1136 {
1137 	switch(li->type) {
1138 	case LTYPE_LOGIN:
1139 		return (wtmp_perform_login(li));
1140 	case LTYPE_LOGOUT:
1141 		return (wtmp_perform_logout(li));
1142 	default:
1143 		logit("%s: invalid type field", __func__);
1144 		return (0);
1145 	}
1146 }
1147 
1148 
1149 /*
1150  * Notes on fetching login data from wtmp/wtmpx
1151  *
1152  * Logouts are usually recorded with (amongst other things) a blank
1153  * username on a given tty line.  However, some systems (HP-UX is one)
1154  * leave all fields set, but change the ut_type field to DEAD_PROCESS.
1155  *
1156  * Since we're only looking for logins here, we know that the username
1157  * must be set correctly. On systems that leave it in, we check for
1158  * ut_type==USER_PROCESS (indicating a login.)
1159  *
1160  * Portability: Some systems may set something other than USER_PROCESS
1161  * to indicate a login process. I don't know of any as I write. Also,
1162  * it's possible that some systems may both leave the username in
1163  * place and not have ut_type.
1164  */
1165 
1166 /* return true if this wtmp entry indicates a login */
1167 static int
1168 wtmp_islogin(struct logininfo *li, struct utmp *ut)
1169 {
1170 	if (strncmp(li->username, ut->ut_name,
1171 	    MIN_SIZEOF(li->username, ut->ut_name)) == 0) {
1172 # ifdef HAVE_TYPE_IN_UTMP
1173 		if (ut->ut_type & USER_PROCESS)
1174 			return (1);
1175 # else
1176 		return (1);
1177 # endif
1178 	}
1179 	return (0);
1180 }
1181 
1182 int
1183 wtmp_get_entry(struct logininfo *li)
1184 {
1185 	struct stat st;
1186 	struct utmp ut;
1187 	int fd, found = 0;
1188 
1189 	/* Clear the time entries in our logininfo */
1190 	li->tv_sec = li->tv_usec = 0;
1191 
1192 	if ((fd = open(WTMP_FILE, O_RDONLY)) < 0) {
1193 		logit("%s: problem opening %s: %s", __func__,
1194 		    WTMP_FILE, strerror(errno));
1195 		return (0);
1196 	}
1197 	if (fstat(fd, &st) != 0) {
1198 		logit("%s: couldn't stat %s: %s", __func__,
1199 		    WTMP_FILE, strerror(errno));
1200 		close(fd);
1201 		return (0);
1202 	}
1203 
1204 	/* Seek to the start of the last struct utmp */
1205 	if (lseek(fd, -(off_t)sizeof(struct utmp), SEEK_END) == -1) {
1206 		/* Looks like we've got a fresh wtmp file */
1207 		close(fd);
1208 		return (0);
1209 	}
1210 
1211 	while (!found) {
1212 		if (atomicio(read, fd, &ut, sizeof(ut)) != sizeof(ut)) {
1213 			logit("%s: read of %s failed: %s", __func__,
1214 			    WTMP_FILE, strerror(errno));
1215 			close (fd);
1216 			return (0);
1217 		}
1218 		if (wtmp_islogin(li, &ut) ) {
1219 			found = 1;
1220 			/*
1221 			 * We've already checked for a time in struct
1222 			 * utmp, in login_getlast()
1223 			 */
1224 # ifdef HAVE_TIME_IN_UTMP
1225 			li->tv_sec = ut.ut_time;
1226 # else
1227 #  if HAVE_TV_IN_UTMP
1228 			li->tv_sec = ut.ut_tv.tv_sec;
1229 #  endif
1230 # endif
1231 			line_fullname(li->line, ut.ut_line,
1232 			    MIN_SIZEOF(li->line, ut.ut_line));
1233 # ifdef HAVE_HOST_IN_UTMP
1234 			strlcpy(li->hostname, ut.ut_host,
1235 			    MIN_SIZEOF(li->hostname, ut.ut_host));
1236 # endif
1237 			continue;
1238 		}
1239 		/* Seek back 2 x struct utmp */
1240 		if (lseek(fd, -(off_t)(2 * sizeof(struct utmp)), SEEK_CUR) == -1) {
1241 			/* We've found the start of the file, so quit */
1242 			close(fd);
1243 			return (0);
1244 		}
1245 	}
1246 
1247 	/* We found an entry. Tidy up and return */
1248 	close(fd);
1249 	return (1);
1250 }
1251 # endif /* USE_WTMP */
1252 
1253 
1254 /**
1255  ** Low-level wtmpx functions
1256  **/
1257 
1258 #ifdef USE_WTMPX
1259 /*
1260  * Write a wtmpx entry direct to the end of the file
1261  * This is a slight modification of code in OpenBSD's logwtmp.c
1262  */
1263 static int
1264 wtmpx_write(struct logininfo *li, struct utmpx *utx)
1265 {
1266 #ifndef HAVE_UPDWTMPX
1267 	struct stat buf;
1268 	int fd, ret = 1;
1269 
1270 	if ((fd = open(WTMPX_FILE, O_WRONLY|O_APPEND, 0)) < 0) {
1271 		logit("%s: problem opening %s: %s", __func__,
1272 		    WTMPX_FILE, strerror(errno));
1273 		return (0);
1274 	}
1275 
1276 	if (fstat(fd, &buf) == 0)
1277 		if (atomicio(vwrite, fd, utx, sizeof(*utx)) != sizeof(*utx)) {
1278 			ftruncate(fd, buf.st_size);
1279 			logit("%s: problem writing %s: %s", __func__,
1280 			    WTMPX_FILE, strerror(errno));
1281 			ret = 0;
1282 		}
1283 	close(fd);
1284 
1285 	return (ret);
1286 #else
1287 	updwtmpx(WTMPX_FILE, utx);
1288 	return (1);
1289 #endif
1290 }
1291 
1292 
1293 static int
1294 wtmpx_perform_login(struct logininfo *li)
1295 {
1296 	struct utmpx utx;
1297 
1298 	construct_utmpx(li, &utx);
1299 	return (wtmpx_write(li, &utx));
1300 }
1301 
1302 
1303 static int
1304 wtmpx_perform_logout(struct logininfo *li)
1305 {
1306 	struct utmpx utx;
1307 
1308 	construct_utmpx(li, &utx);
1309 	return (wtmpx_write(li, &utx));
1310 }
1311 
1312 
1313 int
1314 wtmpx_write_entry(struct logininfo *li)
1315 {
1316 	switch(li->type) {
1317 	case LTYPE_LOGIN:
1318 		return (wtmpx_perform_login(li));
1319 	case LTYPE_LOGOUT:
1320 		return (wtmpx_perform_logout(li));
1321 	default:
1322 		logit("%s: invalid type field", __func__);
1323 		return (0);
1324 	}
1325 }
1326 
1327 /* Please see the notes above wtmp_islogin() for information about the
1328    next two functions */
1329 
1330 /* Return true if this wtmpx entry indicates a login */
1331 static int
1332 wtmpx_islogin(struct logininfo *li, struct utmpx *utx)
1333 {
1334 	if (strncmp(li->username, utx->ut_user,
1335 	    MIN_SIZEOF(li->username, utx->ut_user)) == 0 ) {
1336 # ifdef HAVE_TYPE_IN_UTMPX
1337 		if (utx->ut_type == USER_PROCESS)
1338 			return (1);
1339 # else
1340 		return (1);
1341 # endif
1342 	}
1343 	return (0);
1344 }
1345 
1346 
1347 int
1348 wtmpx_get_entry(struct logininfo *li)
1349 {
1350 	struct stat st;
1351 	struct utmpx utx;
1352 	int fd, found=0;
1353 
1354 	/* Clear the time entries */
1355 	li->tv_sec = li->tv_usec = 0;
1356 
1357 	if ((fd = open(WTMPX_FILE, O_RDONLY)) < 0) {
1358 		logit("%s: problem opening %s: %s", __func__,
1359 		    WTMPX_FILE, strerror(errno));
1360 		return (0);
1361 	}
1362 	if (fstat(fd, &st) != 0) {
1363 		logit("%s: couldn't stat %s: %s", __func__,
1364 		    WTMPX_FILE, strerror(errno));
1365 		close(fd);
1366 		return (0);
1367 	}
1368 
1369 	/* Seek to the start of the last struct utmpx */
1370 	if (lseek(fd, -(off_t)sizeof(struct utmpx), SEEK_END) == -1 ) {
1371 		/* probably a newly rotated wtmpx file */
1372 		close(fd);
1373 		return (0);
1374 	}
1375 
1376 	while (!found) {
1377 		if (atomicio(read, fd, &utx, sizeof(utx)) != sizeof(utx)) {
1378 			logit("%s: read of %s failed: %s", __func__,
1379 			    WTMPX_FILE, strerror(errno));
1380 			close (fd);
1381 			return (0);
1382 		}
1383 		/*
1384 		 * Logouts are recorded as a blank username on a particular
1385 		 * line. So, we just need to find the username in struct utmpx
1386 		 */
1387 		if (wtmpx_islogin(li, &utx)) {
1388 			found = 1;
1389 # if defined(HAVE_TV_IN_UTMPX)
1390 			li->tv_sec = utx.ut_tv.tv_sec;
1391 # elif defined(HAVE_TIME_IN_UTMPX)
1392 			li->tv_sec = utx.ut_time;
1393 # endif
1394 			line_fullname(li->line, utx.ut_line, sizeof(li->line));
1395 # if defined(HAVE_HOST_IN_UTMPX)
1396 			strlcpy(li->hostname, utx.ut_host,
1397 			    MIN_SIZEOF(li->hostname, utx.ut_host));
1398 # endif
1399 			continue;
1400 		}
1401 		if (lseek(fd, -(off_t)(2 * sizeof(struct utmpx)), SEEK_CUR) == -1) {
1402 			close(fd);
1403 			return (0);
1404 		}
1405 	}
1406 
1407 	close(fd);
1408 	return (1);
1409 }
1410 #endif /* USE_WTMPX */
1411 
1412 /**
1413  ** Low-level libutil login() functions
1414  **/
1415 
1416 #ifdef USE_LOGIN
1417 static int
1418 syslogin_perform_login(struct logininfo *li)
1419 {
1420 	struct utmp *ut;
1421 
1422 	ut = xmalloc(sizeof(*ut));
1423 	construct_utmp(li, ut);
1424 	login(ut);
1425 	free(ut);
1426 
1427 	return (1);
1428 }
1429 
1430 static int
1431 syslogin_perform_logout(struct logininfo *li)
1432 {
1433 # ifdef HAVE_LOGOUT
1434 	char line[UT_LINESIZE];
1435 
1436 	(void)line_stripname(line, li->line, sizeof(line));
1437 
1438 	if (!logout(line))
1439 		logit("%s: logout() returned an error", __func__);
1440 #  ifdef HAVE_LOGWTMP
1441 	else
1442 		logwtmp(line, "", "");
1443 #  endif
1444 	/* FIXME: (ATL - if the need arises) What to do if we have
1445 	 * login, but no logout?  what if logout but no logwtmp? All
1446 	 * routines are in libutil so they should all be there,
1447 	 * but... */
1448 # endif
1449 	return (1);
1450 }
1451 
1452 int
1453 syslogin_write_entry(struct logininfo *li)
1454 {
1455 	switch (li->type) {
1456 	case LTYPE_LOGIN:
1457 		return (syslogin_perform_login(li));
1458 	case LTYPE_LOGOUT:
1459 		return (syslogin_perform_logout(li));
1460 	default:
1461 		logit("%s: Invalid type field", __func__);
1462 		return (0);
1463 	}
1464 }
1465 #endif /* USE_LOGIN */
1466 
1467 /* end of file log-syslogin.c */
1468 
1469 /**
1470  ** Low-level lastlog functions
1471  **/
1472 
1473 #ifdef USE_LASTLOG
1474 
1475 #if !defined(LASTLOG_WRITE_PUTUTXLINE) || !defined(HAVE_GETLASTLOGXBYNAME)
1476 /* open the file (using filemode) and seek to the login entry */
1477 static int
1478 lastlog_openseek(struct logininfo *li, int *fd, int filemode)
1479 {
1480 	off_t offset;
1481 	char lastlog_file[1024];
1482 	struct stat st;
1483 
1484 	if (stat(LASTLOG_FILE, &st) != 0) {
1485 		logit("%s: Couldn't stat %s: %s", __func__,
1486 		    LASTLOG_FILE, strerror(errno));
1487 		return (0);
1488 	}
1489 	if (S_ISDIR(st.st_mode)) {
1490 		snprintf(lastlog_file, sizeof(lastlog_file), "%s/%s",
1491 		    LASTLOG_FILE, li->username);
1492 	} else if (S_ISREG(st.st_mode)) {
1493 		strlcpy(lastlog_file, LASTLOG_FILE, sizeof(lastlog_file));
1494 	} else {
1495 		logit("%s: %.100s is not a file or directory!", __func__,
1496 		    LASTLOG_FILE);
1497 		return (0);
1498 	}
1499 
1500 	*fd = open(lastlog_file, filemode, 0600);
1501 	if (*fd < 0) {
1502 		debug("%s: Couldn't open %s: %s", __func__,
1503 		    lastlog_file, strerror(errno));
1504 		return (0);
1505 	}
1506 
1507 	if (S_ISREG(st.st_mode)) {
1508 		/* find this uid's offset in the lastlog file */
1509 		offset = (off_t) ((u_long)li->uid * sizeof(struct lastlog));
1510 
1511 		if (lseek(*fd, offset, SEEK_SET) != offset) {
1512 			logit("%s: %s->lseek(): %s", __func__,
1513 			    lastlog_file, strerror(errno));
1514 			close(*fd);
1515 			return (0);
1516 		}
1517 	}
1518 
1519 	return (1);
1520 }
1521 #endif /* !LASTLOG_WRITE_PUTUTXLINE || !HAVE_GETLASTLOGXBYNAME */
1522 
1523 #ifdef LASTLOG_WRITE_PUTUTXLINE
1524 int
1525 lastlog_write_entry(struct logininfo *li)
1526 {
1527 	switch(li->type) {
1528 	case LTYPE_LOGIN:
1529 		return 1; /* lastlog written by pututxline */
1530 	default:
1531 		logit("lastlog_write_entry: Invalid type field");
1532 		return 0;
1533 	}
1534 }
1535 #else /* LASTLOG_WRITE_PUTUTXLINE */
1536 int
1537 lastlog_write_entry(struct logininfo *li)
1538 {
1539 	struct lastlog last;
1540 	int fd;
1541 
1542 	switch(li->type) {
1543 	case LTYPE_LOGIN:
1544 		/* create our struct lastlog */
1545 		memset(&last, '\0', sizeof(last));
1546 		line_stripname(last.ll_line, li->line, sizeof(last.ll_line));
1547 		strlcpy(last.ll_host, li->hostname,
1548 		    MIN_SIZEOF(last.ll_host, li->hostname));
1549 		last.ll_time = li->tv_sec;
1550 
1551 		if (!lastlog_openseek(li, &fd, O_RDWR|O_CREAT))
1552 			return (0);
1553 
1554 		/* write the entry */
1555 		if (atomicio(vwrite, fd, &last, sizeof(last)) != sizeof(last)) {
1556 			close(fd);
1557 			logit("%s: Error writing to %s: %s", __func__,
1558 			    LASTLOG_FILE, strerror(errno));
1559 			return (0);
1560 		}
1561 
1562 		close(fd);
1563 		return (1);
1564 	default:
1565 		logit("%s: Invalid type field", __func__);
1566 		return (0);
1567 	}
1568 }
1569 #endif /* LASTLOG_WRITE_PUTUTXLINE */
1570 
1571 #ifdef HAVE_GETLASTLOGXBYNAME
1572 int
1573 lastlog_get_entry(struct logininfo *li)
1574 {
1575 	struct lastlogx l, *ll;
1576 
1577 	if ((ll = getlastlogxbyname(li->username, &l)) == NULL) {
1578 		memset(&l, '\0', sizeof(l));
1579 		ll = &l;
1580 	}
1581 	line_fullname(li->line, ll->ll_line, sizeof(li->line));
1582 	strlcpy(li->hostname, ll->ll_host,
1583 		MIN_SIZEOF(li->hostname, ll->ll_host));
1584 	li->tv_sec = ll->ll_tv.tv_sec;
1585 	li->tv_usec = ll->ll_tv.tv_usec;
1586 	return (1);
1587 }
1588 #else /* HAVE_GETLASTLOGXBYNAME */
1589 int
1590 lastlog_get_entry(struct logininfo *li)
1591 {
1592 	struct lastlog last;
1593 	int fd, ret;
1594 
1595 	if (!lastlog_openseek(li, &fd, O_RDONLY))
1596 		return (0);
1597 
1598 	ret = atomicio(read, fd, &last, sizeof(last));
1599 	close(fd);
1600 
1601 	switch (ret) {
1602 	case 0:
1603 		memset(&last, '\0', sizeof(last));
1604 		/* FALLTHRU */
1605 	case sizeof(last):
1606 		line_fullname(li->line, last.ll_line, sizeof(li->line));
1607 		strlcpy(li->hostname, last.ll_host,
1608 		    MIN_SIZEOF(li->hostname, last.ll_host));
1609 		li->tv_sec = last.ll_time;
1610 		return (1);
1611 	case -1:
1612 		error("%s: Error reading from %s: %s", __func__,
1613 		    LASTLOG_FILE, strerror(errno));
1614 		return (0);
1615 	default:
1616 		error("%s: Error reading from %s: Expecting %d, got %d",
1617 		    __func__, LASTLOG_FILE, (int)sizeof(last), ret);
1618 		return (0);
1619 	}
1620 
1621 	/* NOTREACHED */
1622 	return (0);
1623 }
1624 #endif /* HAVE_GETLASTLOGXBYNAME */
1625 #endif /* USE_LASTLOG */
1626 
1627 #if defined(USE_UTMPX) && defined(HAVE_SETUTXDB) && \
1628     defined(UTXDB_LASTLOGIN) && defined(HAVE_GETUTXUSER)
1629 int
1630 utmpx_get_entry(struct logininfo *li)
1631 {
1632 	struct utmpx *utx;
1633 
1634 	if (setutxdb(UTXDB_LASTLOGIN, NULL) != 0)
1635 		return (0);
1636 	utx = getutxuser(li->username);
1637 	if (utx == NULL) {
1638 		endutxent();
1639 		return (0);
1640 	}
1641 
1642 	line_fullname(li->line, utx->ut_line,
1643 	    MIN_SIZEOF(li->line, utx->ut_line));
1644 	strlcpy(li->hostname, utx->ut_host,
1645 	    MIN_SIZEOF(li->hostname, utx->ut_host));
1646 	li->tv_sec = utx->ut_tv.tv_sec;
1647 	li->tv_usec = utx->ut_tv.tv_usec;
1648 	endutxent();
1649 	return (1);
1650 }
1651 #endif /* USE_UTMPX && HAVE_SETUTXDB && UTXDB_LASTLOGIN && HAVE_GETUTXUSER */
1652 
1653 #ifdef USE_BTMP
1654   /*
1655    * Logs failed login attempts in _PATH_BTMP if that exists.
1656    * The most common login failure is to give password instead of username.
1657    * So the _PATH_BTMP file checked for the correct permission, so that
1658    * only root can read it.
1659    */
1660 
1661 void
1662 record_failed_login(struct ssh *ssh, const char *username, const char *hostname,
1663     const char *ttyn)
1664 {
1665 	int fd;
1666 	struct utmp ut;
1667 	struct sockaddr_storage from;
1668 	socklen_t fromlen = sizeof(from);
1669 	struct sockaddr_in *a4;
1670 	struct sockaddr_in6 *a6;
1671 	time_t t;
1672 	struct stat fst;
1673 
1674 	if (geteuid() != 0)
1675 		return;
1676 	if ((fd = open(_PATH_BTMP, O_WRONLY | O_APPEND)) < 0) {
1677 		debug("Unable to open the btmp file %s: %s", _PATH_BTMP,
1678 		    strerror(errno));
1679 		return;
1680 	}
1681 	if (fstat(fd, &fst) < 0) {
1682 		logit("%s: fstat of %s failed: %s", __func__, _PATH_BTMP,
1683 		    strerror(errno));
1684 		goto out;
1685 	}
1686 	if((fst.st_mode & (S_IXGRP | S_IRWXO)) || (fst.st_uid != 0)){
1687 		logit("Excess permission or bad ownership on file %s",
1688 		    _PATH_BTMP);
1689 		goto out;
1690 	}
1691 
1692 	memset(&ut, 0, sizeof(ut));
1693 	/* strncpy because we don't necessarily want nul termination */
1694 	strncpy(ut.ut_user, username, sizeof(ut.ut_user));
1695 	strlcpy(ut.ut_line, "ssh:notty", sizeof(ut.ut_line));
1696 
1697 	time(&t);
1698 	ut.ut_time = t;     /* ut_time is not always a time_t */
1699 	ut.ut_type = LOGIN_PROCESS;
1700 	ut.ut_pid = getpid();
1701 
1702 	/* strncpy because we don't necessarily want nul termination */
1703 	strncpy(ut.ut_host, hostname, sizeof(ut.ut_host));
1704 
1705 	if (ssh_packet_connection_is_on_socket(ssh) &&
1706 	    getpeername(ssh_packet_get_connection_in(ssh),
1707 	    (struct sockaddr *)&from, &fromlen) == 0) {
1708 		ipv64_normalise_mapped(&from, &fromlen);
1709 		if (from.ss_family == AF_INET) {
1710 			a4 = (struct sockaddr_in *)&from;
1711 			memcpy(&ut.ut_addr, &(a4->sin_addr),
1712 			    MIN_SIZEOF(ut.ut_addr, a4->sin_addr));
1713 		}
1714 #ifdef HAVE_ADDR_V6_IN_UTMP
1715 		if (from.ss_family == AF_INET6) {
1716 			a6 = (struct sockaddr_in6 *)&from;
1717 			memcpy(&ut.ut_addr_v6, &(a6->sin6_addr),
1718 			    MIN_SIZEOF(ut.ut_addr_v6, a6->sin6_addr));
1719 		}
1720 #endif
1721 	}
1722 
1723 	if (atomicio(vwrite, fd, &ut, sizeof(ut)) != sizeof(ut))
1724 		error("Failed to write to %s: %s", _PATH_BTMP,
1725 		    strerror(errno));
1726 
1727 out:
1728 	close(fd);
1729 }
1730 #endif	/* USE_BTMP */
1731