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
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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.
29 * The btmp logging code is derived from login.c from util-linux and is under
30 * the the following license:
32 * Copyright (c) 1980, 1987, 1988 The Regents of the University of California.
33 * All rights reserved.
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.
50 ** loginrec.c: platform-independent login recording and lastlog retrieval
54 * The new login code explained
55 * ============================
57 * This code attempts to provide a common interface to login recording
58 * (utmp and friends) and last login time retrieval.
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.
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
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
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
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.
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.
99 * Calling the new code
100 * --------------------
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.
106 * Internal handler calling method
107 * -------------------------------
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.
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.
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.
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,
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.
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.)
145 * Otherwise, patches to the specific method(s) are very helpful!
148 #include "includes.h"
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>
157 #include <netinet/in.h>
172 #include "hostfile.h"
174 #include "loginrec.h"
176 #include "atomicio.h"
178 #include "canohost.h"
188 ** prototypes for helper functions in this file
192 void set_utmp_time(struct logininfo *li, struct utmp *ut);
193 void construct_utmp(struct logininfo *li, struct utmp *ut);
197 void set_utmpx_time(struct logininfo *li, struct utmpx *ut);
198 void construct_utmpx(struct logininfo *li, struct utmpx *ut);
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);
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);
214 extern struct sshbuf *loginmsg;
216 /* pick the shortest string */
217 #define MIN_SIZEOF(s1,s2) (sizeof(s1) < sizeof(s2) ? sizeof(s1) : sizeof(s2))
220 ** platform-independent login functions
224 * login_login(struct logininfo *) - Record a login
226 * Call with a pointer to a struct logininfo initialised with
227 * login_init_entry() or login_alloc_entry()
231 * 0 on failure (will use OpenSSH's logging facilities for diagnostics)
234 login_login(struct logininfo *li)
236 li->type = LTYPE_LOGIN;
237 return (login_write(li));
242 * login_logout(struct logininfo *) - Record a logout
244 * Call as with login_login()
248 * 0 on failure (will use OpenSSH's logging facilities for diagnostics)
251 login_logout(struct logininfo *li)
253 li->type = LTYPE_LOGOUT;
254 return (login_write(li));
258 * login_get_lastlog_time(int) - Retrieve the last login time
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
265 * 0 on failure, or if user has never logged in
266 * Time in seconds from the epoch if successful
268 * Useful preprocessor symbols:
269 * DISABLE_LASTLOG: If set, *never* even try to retrieve lastlog
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.
276 login_get_lastlog_time(const uid_t uid)
280 if (login_get_lastlog(&li, uid))
287 * login_get_lastlog(struct logininfo *, int) - Retrieve a lastlog entry
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.
293 * Note this routine must be given a pre-allocated logininfo.
296 * >0: A pointer to your struct logininfo if successful
297 * 0 on failure (will use OpenSSH's logging facilities for diagnostics)
300 login_get_lastlog(struct logininfo *li, const uid_t uid)
304 memset(li, '\0', sizeof(*li));
308 * If we don't have a 'real' lastlog, we need the username to
309 * reliably search wtmp(x) for the last login (see
314 fatal("%s: Cannot find account for uid %ld", __func__,
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);
325 if (getlast_entry(li))
332 * login_alloc_entry(int, char*, char*, char*) - Allocate and initialise
333 * a logininfo structure
335 * This function creates a new struct logininfo, a data structure
336 * meant to carry the information required to portably record login info.
338 * Returns a pointer to a newly created struct logininfo. If memory
339 * allocation fails, the program halts.
342 logininfo *login_alloc_entry(pid_t pid, const char *username,
343 const char *hostname, const char *line)
345 struct logininfo *newli;
347 newli = xmalloc(sizeof(*newli));
348 login_init_entry(newli, pid, username, hostname, line);
353 /* login_free_entry(struct logininfo *) - free struct memory */
355 login_free_entry(struct logininfo *li)
361 /* login_init_entry(struct logininfo *, int, char*, char*, char*)
362 * - initialise a struct logininfo
364 * Populates a new struct logininfo, a data structure meant to carry
365 * the information required to portably record login info.
370 login_init_entry(struct logininfo *li, pid_t pid, const char *username,
371 const char *hostname, const char *line)
375 memset(li, 0, sizeof(*li));
379 /* set the line information */
381 line_fullname(li->line, line, sizeof(li->line));
384 strlcpy(li->username, username, sizeof(li->username));
385 pw = getpwnam(li->username);
387 fatal("%s: Cannot find user \"%s\"", __func__,
390 li->uid = pw->pw_uid;
394 strlcpy(li->hostname, hostname, sizeof(li->hostname));
400 * login_set_current_time(struct logininfo *) - set the current time
402 * Set the current time in a logininfo structure. This function is
403 * meant to eliminate the need to deal with system dependencies for
407 login_set_current_time(struct logininfo *li)
411 gettimeofday(&tv, NULL);
413 li->tv_sec = tv.tv_sec;
414 li->tv_usec = tv.tv_usec;
417 /* copy a sockaddr_* into our logininfo */
419 login_set_addr(struct logininfo *li, const struct sockaddr *sa,
420 const unsigned int sa_size)
422 unsigned int bufsize = sa_size;
424 /* make sure we don't overrun our union */
425 if (sizeof(li->hostaddr) < sa_size)
426 bufsize = sizeof(li->hostaddr);
428 memcpy(&li->hostaddr.sa, sa, bufsize);
433 ** login_write: Call low-level recording functions based on autoconf
437 login_write(struct logininfo *li)
440 if (geteuid() != 0) {
441 logit("Attempt to write login records by non-root user (aborting)");
446 /* set the timestamp */
447 login_set_current_time(li);
449 syslogin_write_entry(li);
452 if (li->type == LTYPE_LOGIN)
453 lastlog_write_entry(li);
456 utmp_write_entry(li);
459 wtmp_write_entry(li);
462 utmpx_write_entry(li);
465 wtmpx_write_entry(li);
467 #ifdef CUSTOM_SYS_AUTH_RECORD_LOGIN
468 if (li->type == LTYPE_LOGIN &&
469 !sys_auth_record_login(li->username,li->hostname,li->line,
471 logit("Writing login record failed for %s", li->username);
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);
482 #ifdef LOGIN_NEEDS_UTMPX
484 login_utmp_only(struct logininfo *li)
486 li->type = LTYPE_LOGIN;
487 login_set_current_time(li);
489 utmp_write_entry(li);
492 wtmp_write_entry(li);
495 utmpx_write_entry(li);
498 wtmpx_write_entry(li);
505 ** getlast_entry: Call low-level functions to retrieve the last login
509 /* take the uid in li and return the last login time */
511 getlast_entry(struct logininfo *li)
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));
521 #if defined(DISABLE_LASTLOG)
522 /* On some systems we shouldn't even try to obtain last login
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));
534 /* Give up: No means of retrieving last login time */
536 # endif /* DISABLE_LASTLOG */
537 #endif /* USE_LASTLOG */
543 * 'line' string utility functions
545 * These functions process the 'line' string into one of three forms:
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 )
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.
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)
564 line_fullname(char *dst, const char *src, u_int dstsize)
566 memset(dst, '\0', dstsize);
567 if ((strncmp(src, "/dev/", 5) == 0) || (dstsize < (strlen(src) + 5)))
568 strlcpy(dst, src, dstsize);
570 strlcpy(dst, "/dev/", dstsize);
571 strlcat(dst, src, dstsize);
576 /* line_stripname(): strip the leading '/dev' if it exists, return dst */
578 line_stripname(char *dst, const char *src, int dstsize)
580 memset(dst, '\0', dstsize);
581 if (strncmp(src, "/dev/", 5) == 0)
582 strlcpy(dst, src + 5, dstsize);
584 strlcpy(dst, src, dstsize);
589 * line_abbrevname(): Return the abbreviated (usually four-character)
590 * form of the line (Just use the last <dstsize> characters of the
593 * NOTE: use strncpy because we do NOT necessarily want zero
597 line_abbrevname(char *dst, const char *src, int dstsize)
601 memset(dst, '\0', dstsize);
603 /* Always skip prefix if present */
604 if (strncmp(src, "/dev/", 5) == 0)
607 #ifdef WITH_ABBREV_NO_TTY
608 if (strncmp(src, "tty", 3) == 0)
615 if (((int)len - dstsize) > 0)
616 src += ((int)len - dstsize);
618 /* note: _don't_ change this to strlcpy */
619 strncpy(dst, src, (size_t)dstsize);
626 ** utmp utility functions
628 ** These functions manipulate struct utmp, taking system differences
632 #if defined(USE_UTMP) || defined (USE_WTMP) || defined (USE_LOGIN)
634 /* build the utmp structure */
636 set_utmp_time(struct logininfo *li, struct utmp *ut)
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;
647 construct_utmp(struct logininfo *li,
650 # ifdef HAVE_ADDR_V6_IN_UTMP
651 struct sockaddr_in6 *sa6;
654 memset(ut, '\0', sizeof(*ut));
656 /* First fill out fields used for both logins and logouts */
658 # ifdef HAVE_ID_IN_UTMP
659 line_abbrevname(ut->ut_id, li->line, sizeof(ut->ut_id));
662 # ifdef HAVE_TYPE_IN_UTMP
663 /* This is done here to keep utmp constants out of struct logininfo */
666 ut->ut_type = USER_PROCESS;
669 ut->ut_type = DEAD_PROCESS;
673 set_utmp_time(li, ut);
675 line_stripname(ut->ut_line, li->line, sizeof(ut->ut_line));
677 # ifdef HAVE_PID_IN_UTMP
678 ut->ut_pid = li->pid;
681 /* If we're logging out, leave all other fields blank */
682 if (li->type == LTYPE_LOGOUT)
686 * These fields are only used when logging in, and are blank
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));
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;
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;
716 #endif /* USE_UTMP || USE_WTMP || USE_LOGIN */
719 ** utmpx utility functions
721 ** These functions manipulate struct utmpx, accounting for system
725 #if defined(USE_UTMPX) || defined (USE_WTMPX)
726 /* build the utmpx structure */
728 set_utmpx_time(struct logininfo *li, struct utmpx *utx)
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;
739 construct_utmpx(struct logininfo *li, struct utmpx *utx)
741 # ifdef HAVE_ADDR_V6_IN_UTMP
742 struct sockaddr_in6 *sa6;
744 memset(utx, '\0', sizeof(*utx));
746 # ifdef HAVE_ID_IN_UTMPX
747 line_abbrevname(utx->ut_id, li->line, sizeof(utx->ut_id));
750 /* this is done here to keep utmp constants out of loginrec.h */
753 utx->ut_type = USER_PROCESS;
756 utx->ut_type = DEAD_PROCESS;
759 line_stripname(utx->ut_line, li->line, sizeof(utx->ut_line));
760 set_utmpx_time(li, utx);
761 utx->ut_pid = li->pid;
763 /* strncpy(): Don't necessarily want null termination */
764 strncpy(utx->ut_user, li->username,
765 MIN_SIZEOF(utx->ut_user, li->username));
767 if (li->type == LTYPE_LOGOUT)
771 * These fields are only used when logging in, and are blank
775 # ifdef HAVE_HOST_IN_UTMPX
776 strncpy(utx->ut_host, li->hostname,
777 MIN_SIZEOF(utx->ut_host, li->hostname));
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;
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;
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));
802 #endif /* USE_UTMPX || USE_WTMPX */
805 ** Low-level utmp functions
808 /* FIXME: (ATL) utmp_write_direct needs testing */
811 /* if we can, use pututline() etc. */
812 # if !defined(DISABLE_PUTUTLINE) && defined(HAVE_SETUTENT) && \
813 defined(HAVE_PUTUTLINE)
814 # define UTMP_USE_LIBRARY
818 /* write a utmp entry with the system's help (pututline() and pals) */
819 # ifdef UTMP_USE_LIBRARY
821 utmp_write_library(struct logininfo *li, struct utmp *ut)
825 # ifdef HAVE_ENDUTENT
830 # else /* UTMP_USE_LIBRARY */
833 * Write a utmp entry direct to the file
834 * This is a slightly modification of code in OpenBSD's login.c
837 utmp_write_direct(struct logininfo *li, struct utmp *ut)
843 /* FIXME: (ATL) ttyslot() needs local implementation */
845 #if defined(HAVE_GETTTYENT)
850 while (NULL != (ty = getttyent())) {
852 if (!strncmp(ty->ty_name, ut->ut_line, sizeof(ut->ut_line)))
858 logit("%s: tty not found", __func__);
863 tty = ttyslot(); /* seems only to work for /dev/ttyp? style names */
865 #endif /* HAVE_GETTTYENT */
867 if (tty > 0 && (fd = open(UTMP_FILE, O_RDWR|O_CREAT, 0644)) >= 0) {
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));
877 logit("%s: Couldn't seek to tty %d slot in %s",
878 __func__, tty, UTMP_FILE);
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.
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));
893 if ((ret = lseek(fd, pos, SEEK_SET)) == -1) {
894 logit("%s: lseek: %s", __func__, strerror(errno));
899 logit("%s: Couldn't seek to tty %d slot in %s",
900 __func__, tty, UTMP_FILE);
904 if (atomicio(vwrite, fd, ut, sizeof(*ut)) != sizeof(*ut)) {
905 logit("%s: error writing %s: %s", __func__,
906 UTMP_FILE, strerror(errno));
917 # endif /* UTMP_USE_LIBRARY */
920 utmp_perform_login(struct logininfo *li)
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__);
931 if (!utmp_write_direct(li, &ut)) {
932 logit("%s: utmp_write_direct() failed", __func__);
941 utmp_perform_logout(struct logininfo *li)
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__);
952 if (!utmp_write_direct(li, &ut)) {
953 logit("%s: utmp_write_direct() failed", __func__);
962 utmp_write_entry(struct logininfo *li)
966 return (utmp_perform_login(li));
969 return (utmp_perform_logout(li));
972 logit("%s: invalid type field", __func__);
976 #endif /* USE_UTMP */
980 ** Low-level utmpx functions
983 /* not much point if we don't want utmpx entries */
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
993 /* write a utmpx entry with the system's help (pututxline() and pals) */
994 # ifdef UTMPX_USE_LIBRARY
996 utmpx_write_library(struct logininfo *li, struct utmpx *utx)
1001 # ifdef HAVE_ENDUTXENT
1007 # else /* UTMPX_USE_LIBRARY */
1009 /* write a utmp entry direct to the file */
1011 utmpx_write_direct(struct logininfo *li, struct utmpx *utx)
1013 logit("%s: not implemented!", __func__);
1016 # endif /* UTMPX_USE_LIBRARY */
1019 utmpx_perform_login(struct logininfo *li)
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__);
1030 if (!utmpx_write_direct(li, &ut)) {
1031 logit("%s: utmp_write_direct() failed", __func__);
1040 utmpx_perform_logout(struct logininfo *li)
1044 construct_utmpx(li, &utx);
1045 # ifdef HAVE_ID_IN_UTMPX
1046 line_abbrevname(utx.ut_id, li->line, sizeof(utx.ut_id));
1048 # ifdef HAVE_TYPE_IN_UTMPX
1049 utx.ut_type = DEAD_PROCESS;
1052 # ifdef UTMPX_USE_LIBRARY
1053 utmpx_write_library(li, &utx);
1055 utmpx_write_direct(li, &utx);
1061 utmpx_write_entry(struct logininfo *li)
1065 return (utmpx_perform_login(li));
1067 return (utmpx_perform_logout(li));
1069 logit("%s: invalid type field", __func__);
1073 #endif /* USE_UTMPX */
1077 ** Low-level wtmp functions
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
1087 wtmp_write(struct logininfo *li, struct utmp *ut)
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));
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));
1109 wtmp_perform_login(struct logininfo *li)
1113 construct_utmp(li, &ut);
1114 return (wtmp_write(li, &ut));
1119 wtmp_perform_logout(struct logininfo *li)
1123 construct_utmp(li, &ut);
1124 return (wtmp_write(li, &ut));
1129 wtmp_write_entry(struct logininfo *li)
1133 return (wtmp_perform_login(li));
1135 return (wtmp_perform_logout(li));
1137 logit("%s: invalid type field", __func__);
1144 * Notes on fetching login data from wtmp/wtmpx
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.
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.)
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.
1160 /* return true if this wtmp entry indicates a login */
1162 wtmp_islogin(struct logininfo *li, struct utmp *ut)
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)
1177 wtmp_get_entry(struct logininfo *li)
1183 /* Clear the time entries in our logininfo */
1184 li->tv_sec = li->tv_usec = 0;
1186 if ((fd = open(WTMP_FILE, O_RDONLY)) < 0) {
1187 logit("%s: problem opening %s: %s", __func__,
1188 WTMP_FILE, strerror(errno));
1191 if (fstat(fd, &st) != 0) {
1192 logit("%s: couldn't stat %s: %s", __func__,
1193 WTMP_FILE, strerror(errno));
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 */
1206 if (atomicio(read, fd, &ut, sizeof(ut)) != sizeof(ut)) {
1207 logit("%s: read of %s failed: %s", __func__,
1208 WTMP_FILE, strerror(errno));
1212 if (wtmp_islogin(li, &ut) ) {
1215 * We've already checked for a time in struct
1216 * utmp, in login_getlast()
1218 # ifdef HAVE_TIME_IN_UTMP
1219 li->tv_sec = ut.ut_time;
1221 # if HAVE_TV_IN_UTMP
1222 li->tv_sec = ut.ut_tv.tv_sec;
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));
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 */
1241 /* We found an entry. Tidy up and return */
1245 # endif /* USE_WTMP */
1249 ** Low-level wtmpx functions
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
1258 wtmpx_write(struct logininfo *li, struct utmpx *utx)
1260 #ifndef HAVE_UPDWTMPX
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));
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));
1281 updwtmpx(WTMPX_FILE, utx);
1288 wtmpx_perform_login(struct logininfo *li)
1292 construct_utmpx(li, &utx);
1293 return (wtmpx_write(li, &utx));
1298 wtmpx_perform_logout(struct logininfo *li)
1302 construct_utmpx(li, &utx);
1303 return (wtmpx_write(li, &utx));
1308 wtmpx_write_entry(struct logininfo *li)
1312 return (wtmpx_perform_login(li));
1314 return (wtmpx_perform_logout(li));
1316 logit("%s: invalid type field", __func__);
1321 /* Please see the notes above wtmp_islogin() for information about the
1322 next two functions */
1324 /* Return true if this wtmpx entry indicates a login */
1326 wtmpx_islogin(struct logininfo *li, struct utmpx *utx)
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)
1342 wtmpx_get_entry(struct logininfo *li)
1348 /* Clear the time entries */
1349 li->tv_sec = li->tv_usec = 0;
1351 if ((fd = open(WTMPX_FILE, O_RDONLY)) < 0) {
1352 logit("%s: problem opening %s: %s", __func__,
1353 WTMPX_FILE, strerror(errno));
1356 if (fstat(fd, &st) != 0) {
1357 logit("%s: couldn't stat %s: %s", __func__,
1358 WTMPX_FILE, strerror(errno));
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 */
1371 if (atomicio(read, fd, &utx, sizeof(utx)) != sizeof(utx)) {
1372 logit("%s: read of %s failed: %s", __func__,
1373 WTMPX_FILE, strerror(errno));
1378 * Logouts are recorded as a blank username on a particular
1379 * line. So, we just need to find the username in struct utmpx
1381 if (wtmpx_islogin(li, &utx)) {
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;
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));
1395 if (lseek(fd, -(off_t)(2 * sizeof(struct utmpx)), SEEK_CUR) == -1) {
1404 #endif /* USE_WTMPX */
1407 ** Low-level libutil login() functions
1412 syslogin_perform_login(struct logininfo *li)
1416 ut = xmalloc(sizeof(*ut));
1417 construct_utmp(li, ut);
1425 syslogin_perform_logout(struct logininfo *li)
1428 char line[UT_LINESIZE];
1430 (void)line_stripname(line, li->line, sizeof(line));
1433 logit("%s: logout() returned an error", __func__);
1434 # ifdef HAVE_LOGWTMP
1436 logwtmp(line, "", "");
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,
1447 syslogin_write_entry(struct logininfo *li)
1451 return (syslogin_perform_login(li));
1453 return (syslogin_perform_logout(li));
1455 logit("%s: Invalid type field", __func__);
1459 #endif /* USE_LOGIN */
1461 /* end of file log-syslogin.c */
1464 ** Low-level lastlog functions
1469 #if !defined(LASTLOG_WRITE_PUTUTXLINE) || !defined(HAVE_GETLASTLOGXBYNAME)
1470 /* open the file (using filemode) and seek to the login entry */
1472 lastlog_openseek(struct logininfo *li, int *fd, int filemode)
1475 char lastlog_file[1024];
1478 if (stat(LASTLOG_FILE, &st) != 0) {
1479 logit("%s: Couldn't stat %s: %s", __func__,
1480 LASTLOG_FILE, strerror(errno));
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));
1489 logit("%s: %.100s is not a file or directory!", __func__,
1494 *fd = open(lastlog_file, filemode, 0600);
1496 debug("%s: Couldn't open %s: %s", __func__,
1497 lastlog_file, strerror(errno));
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));
1505 if (lseek(*fd, offset, SEEK_SET) != offset) {
1506 logit("%s: %s->lseek(): %s", __func__,
1507 lastlog_file, strerror(errno));
1515 #endif /* !LASTLOG_WRITE_PUTUTXLINE || !HAVE_GETLASTLOGXBYNAME */
1517 #ifdef LASTLOG_WRITE_PUTUTXLINE
1519 lastlog_write_entry(struct logininfo *li)
1523 return 1; /* lastlog written by pututxline */
1525 logit("lastlog_write_entry: Invalid type field");
1529 #else /* LASTLOG_WRITE_PUTUTXLINE */
1531 lastlog_write_entry(struct logininfo *li)
1533 struct lastlog last;
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;
1545 if (!lastlog_openseek(li, &fd, O_RDWR|O_CREAT))
1548 /* write the entry */
1549 if (atomicio(vwrite, fd, &last, sizeof(last)) != sizeof(last)) {
1551 logit("%s: Error writing to %s: %s", __func__,
1552 LASTLOG_FILE, strerror(errno));
1559 logit("%s: Invalid type field", __func__);
1563 #endif /* LASTLOG_WRITE_PUTUTXLINE */
1565 #ifdef HAVE_GETLASTLOGXBYNAME
1567 lastlog_get_entry(struct logininfo *li)
1569 struct lastlogx l, *ll;
1571 if ((ll = getlastlogxbyname(li->username, &l)) == NULL) {
1572 memset(&l, '\0', sizeof(l));
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;
1582 #else /* HAVE_GETLASTLOGXBYNAME */
1584 lastlog_get_entry(struct logininfo *li)
1586 struct lastlog last;
1589 if (!lastlog_openseek(li, &fd, O_RDONLY))
1592 ret = atomicio(read, fd, &last, sizeof(last));
1597 memset(&last, '\0', 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;
1606 error("%s: Error reading from %s: %s", __func__,
1607 LASTLOG_FILE, strerror(errno));
1610 error("%s: Error reading from %s: Expecting %d, got %d",
1611 __func__, LASTLOG_FILE, (int)sizeof(last), ret);
1618 #endif /* HAVE_GETLASTLOGXBYNAME */
1619 #endif /* USE_LASTLOG */
1621 #if defined(USE_UTMPX) && defined(HAVE_SETUTXDB) && \
1622 defined(UTXDB_LASTLOGIN) && defined(HAVE_GETUTXUSER)
1624 utmpx_get_entry(struct logininfo *li)
1628 if (setutxdb(UTXDB_LASTLOGIN, NULL) != 0)
1630 utx = getutxuser(li->username);
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;
1645 #endif /* USE_UTMPX && HAVE_SETUTXDB && UTXDB_LASTLOGIN && HAVE_GETUTXUSER */
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.
1656 record_failed_login(const char *username, const char *hostname,
1661 struct sockaddr_storage from;
1662 socklen_t fromlen = sizeof(from);
1663 struct sockaddr_in *a4;
1664 struct sockaddr_in6 *a6;
1670 if ((fd = open(_PATH_BTMP, O_WRONLY | O_APPEND)) < 0) {
1671 debug("Unable to open the btmp file %s: %s", _PATH_BTMP,
1675 if (fstat(fd, &fst) < 0) {
1676 logit("%s: fstat of %s failed: %s", __func__, _PATH_BTMP,
1680 if((fst.st_mode & (S_IXGRP | S_IRWXO)) || (fst.st_uid != 0)){
1681 logit("Excess permission or bad ownership on file %s",
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));
1692 ut.ut_time = t; /* ut_time is not always a time_t */
1693 ut.ut_type = LOGIN_PROCESS;
1694 ut.ut_pid = getpid();
1696 /* strncpy because we don't necessarily want nul termination */
1697 strncpy(ut.ut_host, hostname, sizeof(ut.ut_host));
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));
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));
1717 if (atomicio(vwrite, fd, &ut, sizeof(ut)) != sizeof(ut))
1718 error("Failed to write to %s: %s", _PATH_BTMP,
1724 #endif /* USE_BTMP */