--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/loginrec.c	Tue Jun 01 02:46:09 2004 +0000
@@ -0,0 +1,1540 @@
+/*
+ * Copyright (c) 2000 Andre Lucas.  All rights reserved.
+ * Portions copyright (c) 1998 Todd C. Miller
+ * Portions copyright (c) 1996 Jason Downs
+ * Portions copyright (c) 1996 Theo de Raadt
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ ** loginrec.c:  platform-independent login recording and lastlog retrieval
+ **/
+
+/*
+  The new login code explained
+  ============================
+
+  This code attempts to provide a common interface to login recording
+  (utmp and friends) and last login time retrieval.
+
+  Its primary means of achieving this is to use 'struct logininfo', a
+  union of all the useful fields in the various different types of
+  system login record structures one finds on UNIX variants.
+
+  We depend on autoconf to define which recording methods are to be
+  used, and which fields are contained in the relevant data structures
+  on the local system. Many C preprocessor symbols affect which code
+  gets compiled here.
+
+  The code is designed to make it easy to modify a particular
+  recording method, without affecting other methods nor requiring so
+  many nested conditional compilation blocks as were commonplace in
+  the old code.
+
+  For login recording, we try to use the local system's libraries as
+  these are clearly most likely to work correctly. For utmp systems
+  this usually means login() and logout() or setutent() etc., probably
+  in libutil, along with logwtmp() etc. On these systems, we fall back
+  to writing the files directly if we have to, though this method
+  requires very thorough testing so we do not corrupt local auditing
+  information. These files and their access methods are very system
+  specific indeed.
+
+  For utmpx systems, the corresponding library functions are
+  setutxent() etc. To the author's knowledge, all utmpx systems have
+  these library functions and so no direct write is attempted. If such
+  a system exists and needs support, direct analogues of the [uw]tmp
+  code should suffice.
+
+  Retrieving the time of last login ('lastlog') is in some ways even
+  more problemmatic than login recording. Some systems provide a
+  simple table of all users which we seek based on uid and retrieve a
+  relatively standard structure. Others record the same information in
+  a directory with a separate file, and others don't record the
+  information separately at all. For systems in the latter category,
+  we look backwards in the wtmp or wtmpx file for the last login entry
+  for our user. Naturally this is slower and on busy systems could
+  incur a significant performance penalty.
+
+  Calling the new code
+  --------------------
+
+  In OpenSSH all login recording and retrieval is performed in
+  login.c. Here you'll find working examples. Also, in the logintest.c
+  program there are more examples.
+
+  Internal handler calling method
+  -------------------------------
+
+  When a call is made to login_login() or login_logout(), both
+  routines set a struct logininfo flag defining which action (log in,
+  or log out) is to be taken. They both then call login_write(), which
+  calls whichever of the many structure-specific handlers autoconf
+  selects for the local system.
+
+  The handlers themselves handle system data structure specifics. Both
+  struct utmp and struct utmpx have utility functions (see
+  construct_utmp*()) to try to make it simpler to add extra systems
+  that introduce new features to either structure.
+
+  While it may seem terribly wasteful to replicate so much similar
+  code for each method, experience has shown that maintaining code to
+  write both struct utmp and utmpx in one function, whilst maintaining
+  support for all systems whether they have library support or not, is
+  a difficult and time-consuming task.
+
+  Lastlog support proceeds similarly. Functions login_get_lastlog()
+  (and its OpenSSH-tuned friend login_get_lastlog_time()) call
+  getlast_entry(), which tries one of three methods to find the last
+  login time. It uses local system lastlog support if it can,
+  otherwise it tries wtmp or wtmpx before giving up and returning 0,
+  meaning "tilt".
+
+  Maintenance
+  -----------
+
+  In many cases it's possible to tweak autoconf to select the correct
+  methods for a particular platform, either by improving the detection
+  code (best), or by presetting DISABLE_<method> or CONF_<method>_FILE
+  symbols for the platform.
+
+  Use logintest to check which symbols are defined before modifying
+  configure.ac and loginrec.c. (You have to build logintest yourself
+  with 'make logintest' as it's not built by default.)
+
+  Otherwise, patches to the specific method(s) are very helpful!
+
+*/
+
+/**
+ ** TODO:
+ **   homegrown ttyslot()
+ **   test, test, test
+ **
+ ** Platform status:
+ ** ----------------
+ **
+ ** Known good:
+ **   Linux (Redhat 6.2, Debian)
+ **   Solaris
+ **   HP-UX 10.20 (gcc only)
+ **   IRIX
+ **   NeXT - M68k/HPPA/Sparc (4.2/3.3)
+ **
+ ** Testing required: Please send reports!
+ **   NetBSD
+ **   HP-UX 11
+ **   AIX
+ **
+ ** Platforms with known problems:
+ **   Some variants of Slackware Linux
+ **
+ **/
+
+/*RCSID("$Id: loginrec.c,v 1.2 2004/05/04 10:17:43 matt Exp $");*/
+
+#include "includes.h"
+#include "loginrec.h"
+#include "dbutil.h"
+#include "atomicio.h"
+
+/**
+ ** prototypes for helper functions in this file
+ **/
+
+#if HAVE_UTMP_H
+void set_utmp_time(struct logininfo *li, struct utmp *ut);
+void construct_utmp(struct logininfo *li, struct utmp *ut);
+#endif
+
+#ifdef HAVE_UTMPX_H
+void set_utmpx_time(struct logininfo *li, struct utmpx *ut);
+void construct_utmpx(struct logininfo *li, struct utmpx *ut);
+#endif
+
+int utmp_write_entry(struct logininfo *li);
+int utmpx_write_entry(struct logininfo *li);
+int wtmp_write_entry(struct logininfo *li);
+int wtmpx_write_entry(struct logininfo *li);
+int lastlog_write_entry(struct logininfo *li);
+int syslogin_write_entry(struct logininfo *li);
+
+int getlast_entry(struct logininfo *li);
+int lastlog_get_entry(struct logininfo *li);
+int wtmp_get_entry(struct logininfo *li);
+int wtmpx_get_entry(struct logininfo *li);
+
+/* pick the shortest string */
+#define MIN_SIZEOF(s1,s2) ( sizeof(s1) < sizeof(s2) ? sizeof(s1) : sizeof(s2) )
+
+/**
+ ** platform-independent login functions
+ **/
+
+/* login_login(struct logininfo *)     -Record a login
+ *
+ * Call with a pointer to a struct logininfo initialised with
+ * login_init_entry() or login_alloc_entry()
+ *
+ * Returns:
+ *  >0 if successful
+ *  0  on failure (will use OpenSSH's logging facilities for diagnostics)
+ */
+int
+login_login (struct logininfo *li)
+{
+	li->type = LTYPE_LOGIN;
+	return login_write(li);
+}
+
+
+/* login_logout(struct logininfo *)     - Record a logout
+ *
+ * Call as with login_login()
+ *
+ * Returns:
+ *  >0 if successful
+ *  0  on failure (will use OpenSSH's logging facilities for diagnostics)
+ */
+int
+login_logout(struct logininfo *li)
+{
+	li->type = LTYPE_LOGOUT;
+	return login_write(li);
+}
+
+/* login_get_lastlog_time(int)           - Retrieve the last login time
+ *
+ * Retrieve the last login time for the given uid. Will try to use the
+ * system lastlog facilities if they are available, but will fall back
+ * to looking in wtmp/wtmpx if necessary
+ *
+ * Returns:
+ *   0 on failure, or if user has never logged in
+ *   Time in seconds from the epoch if successful
+ *
+ * Useful preprocessor symbols:
+ *   DISABLE_LASTLOG: If set, *never* even try to retrieve lastlog
+ *                    info
+ *   USE_LASTLOG: If set, indicates the presence of system lastlog
+ *                facilities. If this and DISABLE_LASTLOG are not set,
+ *                try to retrieve lastlog information from wtmp/wtmpx.
+ */
+unsigned int
+login_get_lastlog_time(const int uid)
+{
+	struct logininfo li;
+
+	if (login_get_lastlog(&li, uid))
+		return li.tv_sec;
+	else
+		return 0;
+}
+
+/* login_get_lastlog(struct logininfo *, int)   - Retrieve a lastlog entry
+ *
+ * Retrieve a logininfo structure populated (only partially) with
+ * information from the system lastlog data, or from wtmp/wtmpx if no
+ * system lastlog information exists.
+ *
+ * Note this routine must be given a pre-allocated logininfo.
+ *
+ * Returns:
+ *  >0: A pointer to your struct logininfo if successful
+ *  0  on failure (will use OpenSSH's logging facilities for diagnostics)
+ *
+ */
+struct logininfo *
+login_get_lastlog(struct logininfo *li, const int uid)
+{
+	struct passwd *pw;
+
+	memset(li, '\0', sizeof(*li));
+	li->uid = uid;
+
+	/*
+	 * If we don't have a 'real' lastlog, we need the username to
+	 * reliably search wtmp(x) for the last login (see
+	 * wtmp_get_entry().)
+	 */
+	pw = getpwuid(uid);
+	if (pw == NULL)
+		dropbear_exit("login_get_lastlog: Cannot find account for uid %i", uid);
+
+	/* No MIN_SIZEOF here - we absolutely *must not* truncate the
+	 * username */
+	strlcpy(li->username, pw->pw_name, sizeof(li->username));
+
+	if (getlast_entry(li))
+		return li;
+	else
+		return NULL;
+}
+
+
+/* login_alloc_entry(int, char*, char*, char*)    - Allocate and initialise
+ *                                                  a logininfo structure
+ *
+ * This function creates a new struct logininfo, a data structure
+ * meant to carry the information required to portably record login info.
+ *
+ * Returns a pointer to a newly created struct logininfo. If memory
+ * allocation fails, the program halts.
+ */
+struct
+logininfo *login_alloc_entry(int pid, const char *username,
+			     const char *hostname, const char *line)
+{
+	struct logininfo *newli;
+
+	newli = (struct logininfo *) m_malloc (sizeof(*newli));
+	(void)login_init_entry(newli, pid, username, hostname, line);
+	return newli;
+}
+
+
+/* login_free_entry(struct logininfo *)    - free struct memory */
+void
+login_free_entry(struct logininfo *li)
+{
+	m_free(li);
+}
+
+
+/* login_init_entry(struct logininfo *, int, char*, char*, char*)
+ *                                        - initialise a struct logininfo
+ *
+ * Populates a new struct logininfo, a data structure meant to carry
+ * the information required to portably record login info.
+ *
+ * Returns: 1
+ */
+int
+login_init_entry(struct logininfo *li, int pid, const char *username,
+		 const char *hostname, const char *line)
+{
+	struct passwd *pw;
+
+	memset(li, 0, sizeof(*li));
+
+	li->pid = pid;
+
+	/* set the line information */
+	if (line)
+		line_fullname(li->line, line, sizeof(li->line));
+
+	if (username) {
+		strlcpy(li->username, username, sizeof(li->username));
+		pw = getpwnam(li->username);
+		if (pw == NULL)
+			dropbear_exit("login_init_entry: Cannot find user \"%s\"",
+					li->username);
+		li->uid = pw->pw_uid;
+	}
+
+	if (hostname)
+		strlcpy(li->hostname, hostname, sizeof(li->hostname));
+
+	return 1;
+}
+
+/* login_set_current_time(struct logininfo *)    - set the current time
+ *
+ * Set the current time in a logininfo structure. This function is
+ * meant to eliminate the need to deal with system dependencies for
+ * time handling.
+ */
+void
+login_set_current_time(struct logininfo *li)
+{
+	struct timeval tv;
+
+	gettimeofday(&tv, NULL);
+
+	li->tv_sec = tv.tv_sec;
+	li->tv_usec = tv.tv_usec;
+}
+
+/* copy a sockaddr_* into our logininfo */
+void
+login_set_addr(struct logininfo *li, const struct sockaddr *sa,
+	       const unsigned int sa_size)
+{
+	unsigned int bufsize = sa_size;
+
+	/* make sure we don't overrun our union */
+	if (sizeof(li->hostaddr) < sa_size)
+		bufsize = sizeof(li->hostaddr);
+
+	memcpy((void *)&(li->hostaddr.sa), (const void *)sa, bufsize);
+}
+
+
+/**
+ ** login_write: Call low-level recording functions based on autoconf
+ ** results
+ **/
+int
+login_write (struct logininfo *li)
+{
+#ifndef HAVE_CYGWIN
+	if ((int)geteuid() != 0) {
+	  dropbear_log(LOG_WARNING,
+			  "Attempt to write login records by non-root user (aborting)");
+	  return 1;
+	}
+#endif
+
+	/* set the timestamp */
+	login_set_current_time(li);
+#ifdef USE_LOGIN
+	syslogin_write_entry(li);
+#endif
+#ifdef USE_LASTLOG
+	if (li->type == LTYPE_LOGIN) {
+		lastlog_write_entry(li);
+	}
+#endif
+#ifdef USE_UTMP
+	utmp_write_entry(li);
+#endif
+#ifdef USE_WTMP
+	wtmp_write_entry(li);
+#endif
+#ifdef USE_UTMPX
+	utmpx_write_entry(li);
+#endif
+#ifdef USE_WTMPX
+	wtmpx_write_entry(li);
+#endif
+	return 0;
+}
+
+#ifdef LOGIN_NEEDS_UTMPX
+int
+login_utmp_only(struct logininfo *li)
+{
+	li->type = LTYPE_LOGIN; 
+	login_set_current_time(li);
+# ifdef USE_UTMP
+	utmp_write_entry(li);
+# endif
+# ifdef USE_WTMP
+	wtmp_write_entry(li);
+# endif
+# ifdef USE_UTMPX
+	utmpx_write_entry(li);
+# endif
+# ifdef USE_WTMPX
+	wtmpx_write_entry(li);
+# endif
+	return 0;
+}
+#endif
+
+/**
+ ** getlast_entry: Call low-level functions to retrieve the last login
+ **                time.
+ **/
+
+/* take the uid in li and return the last login time */
+int
+getlast_entry(struct logininfo *li)
+{
+#ifdef USE_LASTLOG
+	return(lastlog_get_entry(li));
+#else /* !USE_LASTLOG */
+
+#ifdef DISABLE_LASTLOG
+	/* On some systems we shouldn't even try to obtain last login
+	 * time, e.g. AIX */
+	return 0;
+# else /* DISABLE_LASTLOG */
+	/* Try to retrieve the last login time from wtmp */
+#  if defined(USE_WTMP) && (defined(HAVE_STRUCT_UTMP_UT_TIME) || defined(HAVE_STRUCT_UTMP_UT_TV))
+	/* retrieve last login time from utmp */
+	return (wtmp_get_entry(li));
+#  else /* defined(USE_WTMP) && (defined(HAVE_STRUCT_UTMP_UT_TIME) || defined(HAVE_STRUCT_UTMP_UT_TV)) */
+	/* If wtmp isn't available, try wtmpx */
+#   if defined(USE_WTMPX) && (defined(HAVE_STRUCT_UTMPX_UT_TIME) || defined(HAVE_STRUCT_UTMPX_UT_TV))
+	/* retrieve last login time from utmpx */
+	return (wtmpx_get_entry(li));
+#   else
+	/* Give up: No means of retrieving last login time */
+	return 0;
+#   endif /* USE_WTMPX && (HAVE_STRUCT_UTMPX_UT_TIME || HAVE_STRUCT_UTMPX_UT_TV) */
+#  endif /* USE_WTMP && (HAVE_STRUCT_UTMP_UT_TIME || HAVE_STRUCT_UTMP_UT_TV) */
+# endif /* DISABLE_LASTLOG */
+#endif /* USE_LASTLOG */
+}
+
+
+
+/*
+ * 'line' string utility functions
+ *
+ * These functions process the 'line' string into one of three forms:
+ *
+ * 1. The full filename (including '/dev')
+ * 2. The stripped name (excluding '/dev')
+ * 3. The abbreviated name (e.g. /dev/ttyp00 -> yp00
+ *                               /dev/pts/1  -> ts/1 )
+ *
+ * Form 3 is used on some systems to identify a .tmp.? entry when
+ * attempting to remove it. Typically both addition and removal is
+ * performed by one application - say, sshd - so as long as the choice
+ * uniquely identifies a terminal it's ok.
+ */
+
+
+/* line_fullname(): add the leading '/dev/' if it doesn't exist make
+ * sure dst has enough space, if not just copy src (ugh) */
+char *
+line_fullname(char *dst, const char *src, size_t dstsize)
+{
+	memset(dst, '\0', dstsize);
+	if ((strncmp(src, "/dev/", 5) == 0) || (dstsize < (strlen(src) + 5))) {
+		strlcpy(dst, src, dstsize);
+	} else {
+		strlcpy(dst, "/dev/", dstsize);
+		strlcat(dst, src, dstsize);
+	}
+	return dst;
+}
+
+/* line_stripname(): strip the leading '/dev' if it exists, return dst */
+char *
+line_stripname(char *dst, const char *src, size_t dstsize)
+{
+	memset(dst, '\0', dstsize);
+	if (strncmp(src, "/dev/", 5) == 0)
+		strlcpy(dst, src + 5, dstsize);
+	else
+		strlcpy(dst, src, dstsize);
+	return dst;
+}
+
+/* line_abbrevname(): Return the abbreviated (usually four-character)
+ * form of the line (Just use the last <dstsize> characters of the
+ * full name.)
+ *
+ * NOTE: use strncpy because we do NOT necessarily want zero
+ * termination */
+char *
+line_abbrevname(char *dst, const char *src, size_t dstsize)
+{
+	size_t len;
+
+	memset(dst, '\0', dstsize);
+
+	/* Always skip prefix if present */
+	if (strncmp(src, "/dev/", 5) == 0)
+		src += 5;
+
+#ifdef WITH_ABBREV_NO_TTY
+	if (strncmp(src, "tty", 3) == 0)
+		src += 3;
+#endif
+
+	len = strlen(src);
+
+	if (len > 0) {
+		if (((int)len - dstsize) > 0)
+			src +=  ((int)len - dstsize);
+
+		/* note: _don't_ change this to strlcpy */
+		strncpy(dst, src, (size_t)dstsize);
+	}
+
+	return dst;
+}
+
+/**
+ ** utmp utility functions
+ **
+ ** These functions manipulate struct utmp, taking system differences
+ ** into account.
+ **/
+
+#if defined(USE_UTMP) || defined (USE_WTMP) || defined (USE_LOGIN)
+
+/* build the utmp structure */
+void
+set_utmp_time(struct logininfo *li, struct utmp *ut)
+{
+# ifdef HAVE_STRUCT_UTMP_UT_TV
+	ut->ut_tv.tv_sec = li->tv_sec;
+	ut->ut_tv.tv_usec = li->tv_usec;
+# else
+#  ifdef HAVE_STRUCT_UTMP_UT_TIME
+	ut->ut_time = li->tv_sec;
+#  endif
+# endif
+}
+
+void
+construct_utmp(struct logininfo *li,
+		    struct utmp *ut)
+{
+# ifdef HAVE_ADDR_V6_IN_UTMP
+	struct sockaddr_in6 *sa6;
+#  endif
+	memset(ut, '\0', sizeof(*ut));
+
+	/* First fill out fields used for both logins and logouts */
+
+# ifdef HAVE_STRUCT_UTMP_UT_ID
+	line_abbrevname(ut->ut_id, li->line, sizeof(ut->ut_id));
+# endif
+
+# ifdef HAVE_STRUCT_UTMP_UT_TYPE
+	/* This is done here to keep utmp constants out of struct logininfo */
+	switch (li->type) {
+	case LTYPE_LOGIN:
+		ut->ut_type = USER_PROCESS;
+#ifdef _UNICOS
+		cray_set_tmpdir(ut);
+#endif
+		break;
+	case LTYPE_LOGOUT:
+		ut->ut_type = DEAD_PROCESS;
+#ifdef _UNICOS
+		cray_retain_utmp(ut, li->pid);
+#endif
+		break;
+	}
+# endif
+	set_utmp_time(li, ut);
+
+	line_stripname(ut->ut_line, li->line, sizeof(ut->ut_line));
+
+# ifdef HAVE_STRUCT_UTMP_UT_PID
+	ut->ut_pid = li->pid;
+# endif
+
+	/* If we're logging out, leave all other fields blank */
+	if (li->type == LTYPE_LOGOUT)
+	  return;
+
+	/*
+	 * These fields are only used when logging in, and are blank
+	 * for logouts.
+	 */
+
+	/* Use strncpy because we don't necessarily want null termination */
+	strncpy(ut->ut_name, li->username, MIN_SIZEOF(ut->ut_name, li->username));
+# ifdef HAVE_STRUCT_UTMP_UT_HOST
+	strncpy(ut->ut_host, li->hostname, MIN_SIZEOF(ut->ut_host, li->hostname));
+# endif
+# ifdef HAVE_STRUCT_UTMP_UT_ADDR
+	/* this is just a 32-bit IP address */
+	if (li->hostaddr.sa.sa_family == AF_INET)
+		ut->ut_addr = li->hostaddr.sa_in.sin_addr.s_addr;
+# endif
+# ifdef HAVE_ADDR_V6_IN_UTMP
+	/* this is just a 128-bit IPv6 address */
+	if (li->hostaddr.sa.sa_family == AF_INET6) {
+		sa6 = ((struct sockaddr_in6 *)&li->hostaddr.sa);
+		memcpy(ut->ut_addr_v6, sa6->sin6_addr.s6_addr, 16);
+		if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr)) {
+			ut->ut_addr_v6[0] = ut->ut_addr_v6[3];
+			ut->ut_addr_v6[1] = 0;
+			ut->ut_addr_v6[2] = 0;
+			ut->ut_addr_v6[3] = 0;
+		}
+	}
+# endif
+}
+#endif /* USE_UTMP || USE_WTMP || USE_LOGIN */
+
+/**
+ ** utmpx utility functions
+ **
+ ** These functions manipulate struct utmpx, accounting for system
+ ** variations.
+ **/
+
+#if defined(USE_UTMPX) || defined (USE_WTMPX)
+/* build the utmpx structure */
+void
+set_utmpx_time(struct logininfo *li, struct utmpx *utx)
+{
+# ifdef HAVE_STRUCT_UTMPX_UT_TV
+	utx->ut_tv.tv_sec = li->tv_sec;
+	utx->ut_tv.tv_usec = li->tv_usec;
+# else /* HAVE_STRUCT_UTMPX_UT_TV */
+#  ifdef HAVE_STRUCT_UTMPX_UT_TIME
+	utx->ut_time = li->tv_sec;
+#  endif /* HAVE_STRUCT_UTMPX_UT_TIME */
+# endif /* HAVE_STRUCT_UTMPX_UT_TV */
+}
+
+void
+construct_utmpx(struct logininfo *li, struct utmpx *utx)
+{
+# ifdef HAVE_ADDR_V6_IN_UTMP
+	struct sockaddr_in6 *sa6;
+#  endif
+	memset(utx, '\0', sizeof(*utx));
+# ifdef HAVE_STRUCT_UTMPX_UT_ID
+	line_abbrevname(utx->ut_id, li->line, sizeof(utx->ut_id));
+# endif
+
+	/* this is done here to keep utmp constants out of loginrec.h */
+	switch (li->type) {
+	case LTYPE_LOGIN:
+		utx->ut_type = USER_PROCESS;
+		break;
+	case LTYPE_LOGOUT:
+		utx->ut_type = DEAD_PROCESS;
+		break;
+	}
+	line_stripname(utx->ut_line, li->line, sizeof(utx->ut_line));
+	set_utmpx_time(li, utx);
+	utx->ut_pid = li->pid;
+	/* strncpy(): Don't necessarily want null termination */
+	strncpy(utx->ut_name, li->username, MIN_SIZEOF(utx->ut_name, li->username));
+
+	if (li->type == LTYPE_LOGOUT)
+		return;
+
+	/*
+	 * These fields are only used when logging in, and are blank
+	 * for logouts.
+	 */
+
+# ifdef HAVE_STRUCT_UTMPX_UT_HOST
+	strncpy(utx->ut_host, li->hostname, MIN_SIZEOF(utx->ut_host, li->hostname));
+# endif
+# ifdef HAVE_STRUCT_UTMPX_UT_ADDR
+	/* this is just a 32-bit IP address */
+	if (li->hostaddr.sa.sa_family == AF_INET)
+		utx->ut_addr = li->hostaddr.sa_in.sin_addr.s_addr;
+# endif
+# ifdef HAVE_ADDR_V6_IN_UTMP
+	/* this is just a 128-bit IPv6 address */
+	if (li->hostaddr.sa.sa_family == AF_INET6) {
+		sa6 = ((struct sockaddr_in6 *)&li->hostaddr.sa);
+		memcpy(ut->ut_addr_v6, sa6->sin6_addr.s6_addr, 16);
+		if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr)) {
+			ut->ut_addr_v6[0] = ut->ut_addr_v6[3];
+			ut->ut_addr_v6[1] = 0;
+			ut->ut_addr_v6[2] = 0;
+			ut->ut_addr_v6[3] = 0;
+		}
+	}
+# endif
+# ifdef HAVE_STRUCT_UTMPX_UT_SYSLEN
+	/* ut_syslen is the length of the utx_host string */
+	utx->ut_syslen = MIN(strlen(li->hostname), sizeof(utx->ut_host));
+# endif
+}
+#endif /* USE_UTMPX || USE_WTMPX */
+
+/**
+ ** Low-level utmp functions
+ **/
+
+/* FIXME: (ATL) utmp_write_direct needs testing */
+#ifdef USE_UTMP
+
+/* if we can, use pututline() etc. */
+# if !defined(DISABLE_PUTUTLINE) && defined(HAVE_SETUTENT) && \
+	defined(HAVE_PUTUTLINE)
+#  define UTMP_USE_LIBRARY
+# endif
+
+
+/* write a utmp entry with the system's help (pututline() and pals) */
+# ifdef UTMP_USE_LIBRARY
+static int
+utmp_write_library(struct logininfo *li, struct utmp *ut)
+{
+	setutent();
+	pututline(ut);
+
+#  ifdef HAVE_ENDUTENT
+	endutent();
+#  endif
+	return 1;
+}
+# else /* UTMP_USE_LIBRARY */
+
+/* write a utmp entry direct to the file */
+/* This is a slightly modification of code in OpenBSD's login.c */
+static int
+utmp_write_direct(struct logininfo *li, struct utmp *ut)
+{
+	struct utmp old_ut;
+	register int fd;
+	int tty;
+
+	/* FIXME: (ATL) ttyslot() needs local implementation */
+
+#if defined(HAVE_GETTTYENT)
+	register struct ttyent *ty;
+
+	tty=0;
+
+	setttyent();
+	while ((struct ttyent *)0 != (ty = getttyent())) {
+		tty++;
+		if (!strncmp(ty->ty_name, ut->ut_line, sizeof(ut->ut_line)))
+			break;
+	}
+	endttyent();
+
+	if((struct ttyent *)0 == ty) {
+		dropbear_log(LOG_WARNING, "utmp_write_entry: tty not found");
+		return(1);
+	}
+#else /* FIXME */
+
+	tty = ttyslot(); /* seems only to work for /dev/ttyp? style names */
+
+#endif /* HAVE_GETTTYENT */
+
+	if (tty > 0 && (fd = open(UTMP_FILE, O_RDWR|O_CREAT, 0644)) >= 0) {
+		(void)lseek(fd, (off_t)(tty * sizeof(struct utmp)), SEEK_SET);
+		/*
+		 * Prevent luser from zero'ing out ut_host.
+		 * If the new ut_line is empty but the old one is not
+		 * and ut_line and ut_name match, preserve the old ut_line.
+		 */
+		if (atomicio(read, fd, &old_ut, sizeof(old_ut)) == sizeof(old_ut) &&
+			(ut->ut_host[0] == '\0') && (old_ut.ut_host[0] != '\0') &&
+			(strncmp(old_ut.ut_line, ut->ut_line, sizeof(ut->ut_line)) == 0) &&
+			(strncmp(old_ut.ut_name, ut->ut_name, sizeof(ut->ut_name)) == 0)) {
+			(void)memcpy(ut->ut_host, old_ut.ut_host, sizeof(ut->ut_host));
+		}
+
+		(void)lseek(fd, (off_t)(tty * sizeof(struct utmp)), SEEK_SET);
+		if (atomicio(write, fd, ut, sizeof(*ut)) != sizeof(*ut))
+			dropbear_log(LOG_WARNING, "utmp_write_direct: error writing %s: %s",
+			    UTMP_FILE, strerror(errno));
+
+		(void)close(fd);
+		return 1;
+	} else {
+		return 0;
+	}
+}
+# endif /* UTMP_USE_LIBRARY */
+
+static int
+utmp_perform_login(struct logininfo *li)
+{
+	struct utmp ut;
+
+	construct_utmp(li, &ut);
+# ifdef UTMP_USE_LIBRARY
+	if (!utmp_write_library(li, &ut)) {
+		dropbear_log(LOG_WARNING, "utmp_perform_login: utmp_write_library() failed");
+		return 0;
+	}
+# else
+	if (!utmp_write_direct(li, &ut)) {
+		dropbear_log(LOG_WARNING, "utmp_perform_login: utmp_write_direct() failed");
+		return 0;
+	}
+# endif
+	return 1;
+}
+
+
+static int
+utmp_perform_logout(struct logininfo *li)
+{
+	struct utmp ut;
+
+	construct_utmp(li, &ut);
+# ifdef UTMP_USE_LIBRARY
+	if (!utmp_write_library(li, &ut)) {
+		dropbear_log(LOG_WARNING, "utmp_perform_logout: utmp_write_library() failed");
+		return 0;
+	}
+# else
+	if (!utmp_write_direct(li, &ut)) {
+		dropbear_log(LOG_WARNING, "utmp_perform_logout: utmp_write_direct() failed");
+		return 0;
+	}
+# endif
+	return 1;
+}
+
+
+int
+utmp_write_entry(struct logininfo *li)
+{
+	switch(li->type) {
+	case LTYPE_LOGIN:
+		return utmp_perform_login(li);
+
+	case LTYPE_LOGOUT:
+		return utmp_perform_logout(li);
+
+	default:
+		dropbear_log(LOG_WARNING, "utmp_write_entry: invalid type field");
+		return 0;
+	}
+}
+#endif /* USE_UTMP */
+
+
+/**
+ ** Low-level utmpx functions
+ **/
+
+/* not much point if we don't want utmpx entries */
+#ifdef USE_UTMPX
+
+/* if we have the wherewithall, use pututxline etc. */
+# if !defined(DISABLE_PUTUTXLINE) && defined(HAVE_SETUTXENT) && \
+	defined(HAVE_PUTUTXLINE)
+#  define UTMPX_USE_LIBRARY
+# endif
+
+
+/* write a utmpx entry with the system's help (pututxline() and pals) */
+# ifdef UTMPX_USE_LIBRARY
+static int
+utmpx_write_library(struct logininfo *li, struct utmpx *utx)
+{
+	setutxent();
+	pututxline(utx);
+
+#  ifdef HAVE_ENDUTXENT
+	endutxent();
+#  endif
+	return 1;
+}
+
+# else /* UTMPX_USE_LIBRARY */
+
+/* write a utmp entry direct to the file */
+static int
+utmpx_write_direct(struct logininfo *li, struct utmpx *utx)
+{
+	dropbear_log(LOG_WARNING, "utmpx_write_direct: not implemented!");
+	return 0;
+}
+# endif /* UTMPX_USE_LIBRARY */
+
+static int
+utmpx_perform_login(struct logininfo *li)
+{
+	struct utmpx utx;
+
+	construct_utmpx(li, &utx);
+# ifdef UTMPX_USE_LIBRARY
+	if (!utmpx_write_library(li, &utx)) {
+		dropbear_log(LOG_WARNING, "utmpx_perform_login: utmp_write_library() failed");
+		return 0;
+	}
+# else
+	if (!utmpx_write_direct(li, &ut)) {
+		dropbear_log(LOG_WARNING, "utmpx_perform_login: utmp_write_direct() failed");
+		return 0;
+	}
+# endif
+	return 1;
+}
+
+
+static int
+utmpx_perform_logout(struct logininfo *li)
+{
+	struct utmpx utx;
+
+	construct_utmpx(li, &utx);
+# ifdef HAVE_STRUCT_UTMPX_UT_ID
+	line_abbrevname(utx.ut_id, li->line, sizeof(utx.ut_id));
+# endif
+# ifdef HAVE_STRUCT_UTMPX_UT_TYPE
+	utx.ut_type = DEAD_PROCESS;
+# endif
+
+# ifdef UTMPX_USE_LIBRARY
+	utmpx_write_library(li, &utx);
+# else
+	utmpx_write_direct(li, &utx);
+# endif
+	return 1;
+}
+
+int
+utmpx_write_entry(struct logininfo *li)
+{
+	switch(li->type) {
+	case LTYPE_LOGIN:
+		return utmpx_perform_login(li);
+	case LTYPE_LOGOUT:
+		return utmpx_perform_logout(li);
+	default:
+		dropbear_log(LOG_WARNING, "utmpx_write_entry: invalid type field");
+		return 0;
+	}
+}
+#endif /* USE_UTMPX */
+
+
+/**
+ ** Low-level wtmp functions
+ **/
+
+#ifdef USE_WTMP
+
+/* write a wtmp entry direct to the end of the file */
+/* This is a slight modification of code in OpenBSD's logwtmp.c */
+static int
+wtmp_write(struct logininfo *li, struct utmp *ut)
+{
+	struct stat buf;
+	int fd, ret = 1;
+
+	if ((fd = open(WTMP_FILE, O_WRONLY|O_APPEND, 0)) < 0) {
+		dropbear_log(LOG_WARNING, "wtmp_write: problem writing %s: %s",
+		    WTMP_FILE, strerror(errno));
+		return 0;
+	}
+	if (fstat(fd, &buf) == 0)
+		if (atomicio(write, fd, ut, sizeof(*ut)) != sizeof(*ut)) {
+			ftruncate(fd, buf.st_size);
+			dropbear_log(LOG_WARNING, "wtmp_write: problem writing %s: %s",
+			    WTMP_FILE, strerror(errno));
+			ret = 0;
+		}
+	(void)close(fd);
+	return ret;
+}
+
+static int
+wtmp_perform_login(struct logininfo *li)
+{
+	struct utmp ut;
+
+	construct_utmp(li, &ut);
+	return wtmp_write(li, &ut);
+}
+
+
+static int
+wtmp_perform_logout(struct logininfo *li)
+{
+	struct utmp ut;
+
+	construct_utmp(li, &ut);
+	return wtmp_write(li, &ut);
+}
+
+
+int
+wtmp_write_entry(struct logininfo *li)
+{
+	switch(li->type) {
+	case LTYPE_LOGIN:
+		return wtmp_perform_login(li);
+	case LTYPE_LOGOUT:
+		return wtmp_perform_logout(li);
+	default:
+		dropbear_log(LOG_WARNING, "wtmp_write_entry: invalid type field");
+		return 0;
+	}
+}
+
+
+/* Notes on fetching login data from wtmp/wtmpx
+ *
+ * Logouts are usually recorded with (amongst other things) a blank
+ * username on a given tty line.  However, some systems (HP-UX is one)
+ * leave all fields set, but change the ut_type field to DEAD_PROCESS.
+ *
+ * Since we're only looking for logins here, we know that the username
+ * must be set correctly. On systems that leave it in, we check for
+ * ut_type==USER_PROCESS (indicating a login.)
+ *
+ * Portability: Some systems may set something other than USER_PROCESS
+ * to indicate a login process. I don't know of any as I write. Also,
+ * it's possible that some systems may both leave the username in
+ * place and not have ut_type.
+ */
+
+/* return true if this wtmp entry indicates a login */
+static int
+wtmp_islogin(struct logininfo *li, struct utmp *ut)
+{
+	if (strncmp(li->username, ut->ut_name,
+		MIN_SIZEOF(li->username, ut->ut_name)) == 0) {
+# ifdef HAVE_STRUCT_UTMP_UT_TYPE
+		if (ut->ut_type & USER_PROCESS)
+			return 1;
+# else
+		return 1;
+# endif
+	}
+	return 0;
+}
+
+int
+wtmp_get_entry(struct logininfo *li)
+{
+	struct stat st;
+	struct utmp ut;
+	int fd, found=0;
+
+	/* Clear the time entries in our logininfo */
+	li->tv_sec = li->tv_usec = 0;
+
+	if ((fd = open(WTMP_FILE, O_RDONLY)) < 0) {
+		dropbear_log(LOG_WARNING, "wtmp_get_entry: problem opening %s: %s",
+		    WTMP_FILE, strerror(errno));
+		return 0;
+	}
+	if (fstat(fd, &st) != 0) {
+		dropbear_log(LOG_WARNING, "wtmp_get_entry: couldn't stat %s: %s",
+		    WTMP_FILE, strerror(errno));
+		close(fd);
+		return 0;
+	}
+
+	/* Seek to the start of the last struct utmp */
+	if (lseek(fd, -(off_t)sizeof(struct utmp), SEEK_END) == -1) {
+		/* Looks like we've got a fresh wtmp file */
+		close(fd);
+		return 0;
+	}
+
+	while (!found) {
+		if (atomicio(read, fd, &ut, sizeof(ut)) != sizeof(ut)) {
+			dropbear_log(LOG_WARNING, "wtmp_get_entry: read of %s failed: %s",
+			    WTMP_FILE, strerror(errno));
+			close (fd);
+			return 0;
+		}
+		if ( wtmp_islogin(li, &ut) ) {
+			found = 1;
+			/* We've already checked for a time in struct
+			 * utmp, in login_getlast(). */
+# ifdef HAVE_STRUCT_UTMP_UT_TIME
+			li->tv_sec = ut.ut_time;
+# else
+#  if HAVE_STRUCT_UTMP_UT_TV
+			li->tv_sec = ut.ut_tv.tv_sec;
+#  endif
+# endif
+			line_fullname(li->line, ut.ut_line,
+				      MIN_SIZEOF(li->line, ut.ut_line));
+# ifdef HAVE_STRUCT_UTMP_UT_HOST
+			strlcpy(li->hostname, ut.ut_host,
+				MIN_SIZEOF(li->hostname, ut.ut_host));
+# endif
+			continue;
+		}
+		/* Seek back 2 x struct utmp */
+		if (lseek(fd, -(off_t)(2 * sizeof(struct utmp)), SEEK_CUR) == -1) {
+			/* We've found the start of the file, so quit */
+			close (fd);
+			return 0;
+		}
+	}
+
+	/* We found an entry. Tidy up and return */
+	close(fd);
+	return 1;
+}
+# endif /* USE_WTMP */
+
+
+/**
+ ** Low-level wtmpx functions
+ **/
+
+#ifdef USE_WTMPX
+/* write a wtmpx entry direct to the end of the file */
+/* This is a slight modification of code in OpenBSD's logwtmp.c */
+static int
+wtmpx_write(struct logininfo *li, struct utmpx *utx)
+{
+	struct stat buf;
+	int fd, ret = 1;
+
+	if ((fd = open(WTMPX_FILE, O_WRONLY|O_APPEND, 0)) < 0) {
+		dropbear_log(LOG_WARNING, "wtmpx_write: problem opening %s: %s",
+		    WTMPX_FILE, strerror(errno));
+		return 0;
+	}
+
+	if (fstat(fd, &buf) == 0)
+		if (atomicio(write, fd, utx, sizeof(*utx)) != sizeof(*utx)) {
+			ftruncate(fd, buf.st_size);
+			dropbear_log(LOG_WARNING, "wtmpx_write: problem writing %s: %s",
+			    WTMPX_FILE, strerror(errno));
+			ret = 0;
+		}
+	(void)close(fd);
+
+	return ret;
+}
+
+
+static int
+wtmpx_perform_login(struct logininfo *li)
+{
+	struct utmpx utx;
+
+	construct_utmpx(li, &utx);
+	return wtmpx_write(li, &utx);
+}
+
+
+static int
+wtmpx_perform_logout(struct logininfo *li)
+{
+	struct utmpx utx;
+
+	construct_utmpx(li, &utx);
+	return wtmpx_write(li, &utx);
+}
+
+
+int
+wtmpx_write_entry(struct logininfo *li)
+{
+	switch(li->type) {
+	case LTYPE_LOGIN:
+		return wtmpx_perform_login(li);
+	case LTYPE_LOGOUT:
+		return wtmpx_perform_logout(li);
+	default:
+		dropbear_log(LOG_WARNING, "wtmpx_write_entry: invalid type field");
+		return 0;
+	}
+}
+
+/* Please see the notes above wtmp_islogin() for information about the
+   next two functions */
+
+/* Return true if this wtmpx entry indicates a login */
+static int
+wtmpx_islogin(struct logininfo *li, struct utmpx *utx)
+{
+	if ( strncmp(li->username, utx->ut_name,
+		MIN_SIZEOF(li->username, utx->ut_name)) == 0 ) {
+# ifdef HAVE_STRUCT_UTMPX_UT_TYPE
+		if (utx->ut_type == USER_PROCESS)
+			return 1;
+# else
+		return 1;
+# endif
+	}
+	return 0;
+}
+
+
+int
+wtmpx_get_entry(struct logininfo *li)
+{
+	struct stat st;
+	struct utmpx utx;
+	int fd, found=0;
+
+	/* Clear the time entries */
+	li->tv_sec = li->tv_usec = 0;
+
+	if ((fd = open(WTMPX_FILE, O_RDONLY)) < 0) {
+		dropbear_log(LOG_WARNING, "wtmpx_get_entry: problem opening %s: %s",
+		    WTMPX_FILE, strerror(errno));
+		return 0;
+	}
+	if (fstat(fd, &st) != 0) {
+		dropbear_log(LOG_WARNING, "wtmpx_get_entry: couldn't stat %s: %s",
+		    WTMPX_FILE, strerror(errno));
+		close(fd);
+		return 0;
+	}
+
+	/* Seek to the start of the last struct utmpx */
+	if (lseek(fd, -(off_t)sizeof(struct utmpx), SEEK_END) == -1 ) {
+		/* probably a newly rotated wtmpx file */
+		close(fd);
+		return 0;
+	}
+
+	while (!found) {
+		if (atomicio(read, fd, &utx, sizeof(utx)) != sizeof(utx)) {
+			dropbear_log(LOG_WARNING, "wtmpx_get_entry: read of %s failed: %s",
+			    WTMPX_FILE, strerror(errno));
+			close (fd);
+			return 0;
+		}
+		/* Logouts are recorded as a blank username on a particular line.
+		 * So, we just need to find the username in struct utmpx */
+		if ( wtmpx_islogin(li, &utx) ) {
+			found = 1;
+# ifdef HAVE_STRUCT_UTMPX_UT_TV
+			li->tv_sec = utx.ut_tv.tv_sec;
+# else
+#  ifdef HAVE_STRUCT_UTMPX_UT_TIME
+			li->tv_sec = utx.ut_time;
+#  endif
+# endif
+			line_fullname(li->line, utx.ut_line, sizeof(li->line));
+# ifdef HAVE_STRUCT_UTMPX_UT_HOST
+			strlcpy(li->hostname, utx.ut_host,
+				MIN_SIZEOF(li->hostname, utx.ut_host));
+# endif
+			continue;
+		}
+		if (lseek(fd, -(off_t)(2 * sizeof(struct utmpx)), SEEK_CUR) == -1) {
+			close (fd);
+			return 0;
+		}
+	}
+
+	close(fd);
+	return 1;
+}
+#endif /* USE_WTMPX */
+
+/**
+ ** Low-level libutil login() functions
+ **/
+
+#ifdef USE_LOGIN
+static int
+syslogin_perform_login(struct logininfo *li)
+{
+	struct utmp *ut;
+
+	if (! (ut = (struct utmp *)malloc(sizeof(*ut)))) {
+		dropbear_log(LOG_WARNING, "syslogin_perform_login: couldn't malloc()");
+		return 0;
+	}
+	construct_utmp(li, ut);
+	login(ut);
+	free(ut);
+
+	return 1;
+}
+
+static int
+syslogin_perform_logout(struct logininfo *li)
+{
+# ifdef HAVE_LOGOUT
+	char line[8];
+
+	(void)line_stripname(line, li->line, sizeof(line));
+
+	if (!logout(line)) {
+		dropbear_log(LOG_WARNING, "syslogin_perform_logout: logout(%s) returned an error: %s", line, strerror(errno));
+#  ifdef HAVE_LOGWTMP
+	} else {
+		logwtmp(line, "", "");
+#  endif
+	}
+	/* FIXME: (ATL - if the need arises) What to do if we have
+	 * login, but no logout?  what if logout but no logwtmp? All
+	 * routines are in libutil so they should all be there,
+	 * but... */
+# endif
+	return 1;
+}
+
+int
+syslogin_write_entry(struct logininfo *li)
+{
+	switch (li->type) {
+	case LTYPE_LOGIN:
+		return syslogin_perform_login(li);
+	case LTYPE_LOGOUT:
+		return syslogin_perform_logout(li);
+	default:
+		dropbear_log(LOG_WARNING, "syslogin_write_entry: Invalid type field");
+		return 0;
+	}
+}
+#endif /* USE_LOGIN */
+
+/* end of file log-syslogin.c */
+
+/**
+ ** Low-level lastlog functions
+ **/
+
+#ifdef USE_LASTLOG
+#define LL_FILE 1
+#define LL_DIR 2
+#define LL_OTHER 3
+
+static void
+lastlog_construct(struct logininfo *li, struct lastlog *last)
+{
+	/* clear the structure */
+	memset(last, '\0', sizeof(*last));
+
+	(void)line_stripname(last->ll_line, li->line, sizeof(last->ll_line));
+	strlcpy(last->ll_host, li->hostname,
+		MIN_SIZEOF(last->ll_host, li->hostname));
+	last->ll_time = li->tv_sec;
+}
+
+static int
+lastlog_filetype(char *filename)
+{
+	struct stat st;
+
+	if (stat(LASTLOG_FILE, &st) != 0) {
+		dropbear_log(LOG_WARNING, "lastlog_perform_login: Couldn't stat %s: %s", LASTLOG_FILE,
+			strerror(errno));
+		return 0;
+	}
+	if (S_ISDIR(st.st_mode))
+		return LL_DIR;
+	else if (S_ISREG(st.st_mode))
+		return LL_FILE;
+	else
+		return LL_OTHER;
+}
+
+
+/* open the file (using filemode) and seek to the login entry */
+static int
+lastlog_openseek(struct logininfo *li, int *fd, int filemode)
+{
+	off_t offset;
+	int type;
+	char lastlog_file[1024];
+
+	type = lastlog_filetype(LASTLOG_FILE);
+	switch (type) {
+		case LL_FILE:
+			strlcpy(lastlog_file, LASTLOG_FILE, sizeof(lastlog_file));
+			break;
+		case LL_DIR:
+			snprintf(lastlog_file, sizeof(lastlog_file), "%s/%s",
+				 LASTLOG_FILE, li->username);
+			break;
+		default:
+			dropbear_log(LOG_WARNING, "lastlog_openseek: %.100s is not a file or directory!",
+			    LASTLOG_FILE);
+			return 0;
+	}
+
+	*fd = open(lastlog_file, filemode);
+	if ( *fd < 0) {
+		dropbear_log(LOG_INFO, "lastlog_openseek: Couldn't open %s: %s",
+		    lastlog_file, strerror(errno));
+		return 0;
+	}
+
+	if (type == LL_FILE) {
+		/* find this uid's offset in the lastlog file */
+		offset = (off_t) ((long)li->uid * sizeof(struct lastlog));
+
+		if ( lseek(*fd, offset, SEEK_SET) != offset ) {
+			dropbear_log(LOG_WARNING, "lastlog_openseek: %s->lseek(): %s",
+			 lastlog_file, strerror(errno));
+			return 0;
+		}
+	}
+
+	return 1;
+}
+
+static int
+lastlog_perform_login(struct logininfo *li)
+{
+	struct lastlog last;
+	int fd;
+
+	/* create our struct lastlog */
+	lastlog_construct(li, &last);
+
+	if (!lastlog_openseek(li, &fd, O_RDWR|O_CREAT))
+		return(0);
+
+	/* write the entry */
+	if (atomicio(write, fd, &last, sizeof(last)) != sizeof(last)) {
+		close(fd);
+		dropbear_log(LOG_WARNING, "lastlog_write_filemode: Error writing to %s: %s",
+		    LASTLOG_FILE, strerror(errno));
+		return 0;
+	}
+
+	close(fd);
+	return 1;
+}
+
+int
+lastlog_write_entry(struct logininfo *li)
+{
+	switch(li->type) {
+	case LTYPE_LOGIN:
+		return lastlog_perform_login(li);
+	default:
+		dropbear_log(LOG_WARNING, "lastlog_write_entry: Invalid type field");
+		return 0;
+	}
+}
+
+static void
+lastlog_populate_entry(struct logininfo *li, struct lastlog *last)
+{
+	line_fullname(li->line, last->ll_line, sizeof(li->line));
+	strlcpy(li->hostname, last->ll_host,
+		MIN_SIZEOF(li->hostname, last->ll_host));
+	li->tv_sec = last->ll_time;
+}
+
+int
+lastlog_get_entry(struct logininfo *li)
+{
+	struct lastlog last;
+	int fd, ret;
+
+	if (!lastlog_openseek(li, &fd, O_RDONLY))
+		return (0);
+
+	ret = atomicio(read, fd, &last, sizeof(last));
+	close(fd);
+
+	switch (ret) {
+	case 0:
+		memset(&last, '\0', sizeof(last));
+		/* FALLTHRU */
+	case sizeof(last):
+		lastlog_populate_entry(li, &last);
+		return (1);
+	case -1:
+		dropbear_log(LOG_ERR, "Error reading from %s: %s",
+		    LASTLOG_FILE, strerror(errno));
+		return (0);
+	default:
+		dropbear_log(LOG_ERR, "Error reading from %s: Expecting %d, got %d",
+		    LASTLOG_FILE, sizeof(last), ret);
+		return (0);
+	}
+
+	/* NOTREACHED */
+	return (0);
+}
+#endif /* USE_LASTLOG */