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
login_login(struct logininfo * li)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
login_logout(struct logininfo * li)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
login_get_lastlog_time(const uid_t uid)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 *
login_get_lastlog(struct logininfo * li,const uid_t uid)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
login_alloc_entry(pid_t pid,const char * username,const char * hostname,const char * line)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
login_free_entry(struct logininfo * li)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
login_init_entry(struct logininfo * li,pid_t pid,const char * username,const char * hostname,const char * line)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
login_set_current_time(struct logininfo * li)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
login_set_addr(struct logininfo * li,const struct sockaddr * sa,const unsigned int sa_size)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
login_write(struct logininfo * li)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
login_utmp_only(struct logininfo * li)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
getlast_entry(struct logininfo * li)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 *
line_fullname(char * dst,const char * src,u_int dstsize)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 *
line_stripname(char * dst,const char * src,int dstsize)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 *
line_abbrevname(char * dst,const char * src,int dstsize)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
set_utmp_time(struct logininfo * li,struct utmp * ut)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
construct_utmp(struct logininfo * li,struct utmp * ut)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 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
set_utmpx_time(struct logininfo * li,struct utmpx * utx)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
construct_utmpx(struct logininfo * li,struct utmpx * utx)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
utmp_write_library(struct logininfo * li,struct utmp * ut)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
utmp_write_direct(struct logininfo * li,struct utmp * ut)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
utmp_perform_login(struct logininfo * li)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
utmp_perform_logout(struct logininfo * li)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
utmp_write_entry(struct logininfo * li)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
utmpx_write_library(struct logininfo * li,struct utmpx * utx)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
utmpx_write_direct(struct logininfo * li,struct utmpx * utx)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
utmpx_perform_login(struct logininfo * li)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
utmpx_perform_logout(struct logininfo * li)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
utmpx_write_entry(struct logininfo * li)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
wtmp_write(struct logininfo * li,struct utmp * ut)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
wtmp_perform_login(struct logininfo * li)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
wtmp_perform_logout(struct logininfo * li)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
wtmp_write_entry(struct logininfo * li)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
wtmp_islogin(struct logininfo * li,struct utmp * ut)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
wtmp_get_entry(struct logininfo * li)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
wtmpx_write(struct logininfo * li,struct utmpx * utx)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
wtmpx_perform_login(struct logininfo * li)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
wtmpx_perform_logout(struct logininfo * li)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
wtmpx_write_entry(struct logininfo * li)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
wtmpx_islogin(struct logininfo * li,struct utmpx * utx)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
wtmpx_get_entry(struct logininfo * li)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
syslogin_perform_login(struct logininfo * li)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
syslogin_perform_logout(struct logininfo * li)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
syslogin_write_entry(struct logininfo * li)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
lastlog_openseek(struct logininfo * li,int * fd,int filemode)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
lastlog_write_entry(struct logininfo * li)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
lastlog_write_entry(struct logininfo * li)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
lastlog_get_entry(struct logininfo * li)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
lastlog_get_entry(struct logininfo * li)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
utmpx_get_entry(struct logininfo * li)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
record_failed_login(const char * username,const char * hostname,const char * ttyn)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