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