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