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