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