Many changes to new login code based on Damien's feedback:

- Removed many redundant accessor/mutator methods as they're not necesary
   in OpenSSH
- Added proper credits for OpenBSD code in loginrec.c
- Changed function definitions to the OpenBSD style
- Removed spurious 'L' prefix in line filename abbreviation for ut_line
- Added some documentation in loginrec.c
- Changed lastlog access function names
- Removed #include lines in mid-file loginrec.c
- loginrec.h, login.c and logintest.c changed to reflect new interface
- Added TODO note for ttyslot() replacement

1 files changed, 380 insertions, 425 deletions

diff --git a/loginrec.c b/loginrec.c
index 3991d91c5..ed14f3a74 100644
--- a/loginrec.c
+++ b/loginrec.c
@@ -1,5 +1,8 @@
 /*
  * 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
@@ -31,9 +34,106 @@
  ** 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.in 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:
- **   sockaddr_* stuff isn't finished
+ **   homegrown ttyslot()q
+ **   test, test, test
  **
  ** Platform status:
  ** ----------------
@@ -66,19 +166,28 @@
 #include <stdio.h>
 #include <errno.h>
 #ifdef HAVE_PWD_H
-# include <pwd.h>
+#  include <pwd.h>
 #endif
 #ifdef HAVE_SYS_TIME_H
 #  include <sys/time.h>
 #else
 #  include <time.h>
 #endif
+#if HAVE_UTMP_H
+# include <utmp.h>
+#endif
+#if HAVE_UTMPX_H
+# include <utmpx.h>
+#endif
+#if HAVE_LASTLOG_H
+# include <lastlog.h>
+#endif
 
 #include "ssh.h"
 #include "xmalloc.h"
 #include "loginrec.h"
 
-RCSID("$Id: loginrec.c,v 1.2 2000/06/03 16:18:19 andre Exp $");
+RCSID("$Id: loginrec.c,v 1.3 2000/06/04 17:07:49 andre Exp $");
 
 
 /**
@@ -86,13 +195,11 @@ RCSID("$Id: loginrec.c,v 1.2 2000/06/03 16:18:19 andre Exp $");
  **/
 
 #if HAVE_UTMP_H
-# include <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
-# include <utmpx.h>
 void set_utmpx_time(struct logininfo *li, struct utmpx *ut);
 void construct_utmpx(struct logininfo *li, struct utmpx *ut);
 #endif
@@ -114,169 +221,128 @@ int wtmpx_get_entry(struct logininfo *li);
  ** platform-independent login functions
  **/
 
-/* login_alloc_entry()    - allocate and initialise a logininfo */
-struct logininfo *login_alloc_entry(int pid, const char *username,
-                                       const char *hostname,
-                                       const char *line) {
-        struct logininfo *newli;
-
-        newli = (struct logininfo *) xmalloc (sizeof(struct logininfo));
-
-        if (login_init_entry(newli, pid, username, hostname, line))
-                return newli;
-        else
-                return 0;     /* fail */
-} /* login_alloc_entry() */
-
-
-/* login_free_entry()    - free struct memory (duh) */
-void login_free_entry(struct logininfo *li) {
-        if (li && (li->line[0] != '\0'))
-                free ((void *)li);
-        else
-          log("login_free_entry: attempt to free invalid entry (warning)");
-} /* login_free_entry() */
-
-/* login_init_entry()   - initialise a struct logininfo */
-int login_init_entry(struct logininfo *li,
-                        int pid, const char *username, 
-                        const char *hostname, const char *line) {
-
-        /* zero the structure */
-        memset(li, 0, sizeof(struct logininfo));
-  
-        /* progname should be set outside this call */
-        /* type stays null by default */
-        login_set_pid(li, pid);
-        /* set the line information */
-        login_set_line(li, line);
-        login_set_username(li, username);
-        login_set_hostname(li, hostname);
-        /* exit status and termination stay null by default */
-        login_set_current_time(li);
-        /* sockaddr_* stuff must be set separately (for now) */
-        return 1;
-} /* login_init_entry() */
+/* Record a login */
+int
+login_login (struct logininfo *li)
+{
+        li->type = LTYPE_LOGIN;
+        return login_write(li);
+}
 
 
-void
-login_set_progname(struct logininfo *li, const char *progname) {
-        memset(li->progname, '\0', sizeof(li->progname));
-        if (progname)
-                strlcpy(li->progname, progname, sizeof(li->progname));
-        else
-                li->progname[0] = '\0';   /* set to null */
+/* Record a logout */
+int
+login_logout(struct logininfo *li)
+{
+        li->type = LTYPE_LOGOUT;
+        return login_write(li);
 }
 
-void
-login_set_type(struct logininfo *li, int type) {
-        li->type = type;
-}
 
-void
-login_set_pid(struct logininfo *li, int pid) {
-        if (!pid)
-                li->pid = (int)getpid();
-        else
-                li->pid = pid;
-}
+/* Retrieve the last login time for a user (or fake on from wtmp/wtmpx) */
+unsigned int
+login_get_lastlog_time(const int uid)
+{
+        struct logininfo li;
 
-void
-login_set_uid(struct logininfo *li, int uid) {
-        struct passwd *pw;
+        login_get_lastlog(&li, uid);
+        return li.tv_sec;
+}
 
+/* Retrieve a lastlog entry (or fake one from wtmp/wtmpx) */
+struct logininfo *
+login_get_lastlog(struct logininfo *li, const int uid)
+{
+        memset(li, '\0', sizeof(struct logininfo));
         li->uid = uid;
-        /* now update the username */
-        pw = getpwuid(uid);
-        strlcpy(li->username, pw->pw_name, sizeof(li->username));
+        if (getlast_entry(li))
+                return li;
+        else
+                return 0;
 }
 
-void
-login_set_line(struct logininfo *li, const char *line) {
-        if (line) {
-                /* canonical form is the full name, i.e. including '/dev' */
-                line_fullname(li->line, line, sizeof(li->line));
-        } else
-                li->line[0] = '\0';
-}
 
-void
-login_set_username(struct logininfo *li, const char *username) {
-        struct passwd *pw;
+/* login_alloc_entry()    - allocate and initialise a logininfo */
+struct
+logininfo *login_alloc_entry(int pid, const char *username,
+                             const char *hostname, const char *line)
+{
+        struct logininfo *newli;
 
-        if (!username) {
-                li->username[0] = '\0';
-                li->uid = -1;  /* hmm... */
-        } else {
-                strlcpy(li->username, username, sizeof(li->username));
-                /* now update the uid */
-                pw = getpwnam(username);
-                li->uid = pw->pw_uid;
-        }
+        newli = (struct logininfo *) xmalloc (sizeof(struct logininfo));
+        (void)login_init_entry(newli, pid, username, hostname, line);
+        return newli;
 }
 
 
+/* login_free_entry()    - free struct memory (trivial) */
 void
-login_set_hostname(struct logininfo *li, const char *hostname) {
-        if (hostname) { /* can be null */
-                strlcpy(li->hostname, hostname, sizeof(li->hostname));
-        } 
+login_free_entry(struct logininfo *li)
+{
+        xfree(li);
 }
 
 
-void
-login_set_exitstatus(struct logininfo *li,
-                          int exit, int termination) {
-        /* FIXME: (ATL) And? */
-}
-
+/* login_init_entry()   - initialise a struct logininfo */
+int
+login_init_entry(struct logininfo *li, int pid, const char *username, 
+                 const char *hostname, const char *line)
+{
+        /* zero the structure */
+        memset(li, 0, sizeof(struct logininfo));
+  
+        li->pid = pid;
+        /* set the line information */
+        if (line)
+                line_fullname(li->line, line, sizeof(li->line));
 
-/* tv_usec should be null on systems without struct timeval */
-void
-login_set_time(struct logininfo *li,
-                    unsigned int tv_sec, unsigned int tv_usec) {
-        li->tv_sec = tv_sec;
-        li->tv_usec = tv_usec;
+        if (username)
+                strlcpy(li->username, username, sizeof(li->username));
+        if (hostname)
+                strlcpy(li->hostname, hostname, sizeof(li->hostname));
+        return 1;
 }
 
 
 void
-login_set_current_time(struct logininfo *li) {
+login_set_current_time(struct logininfo *li)
+{
 #ifdef HAVE_SYS_TIME_H
         struct timeval tv;
 
         gettimeofday(&tv, NULL);
         li->tv_sec = tv.tv_sec ; li->tv_usec = tv.tv_usec;
 #else
-        time_t t = time(0);
-  
-        li->tv_sec = t; li->tv_usec = 0;
+        time_t tm = time(0);
+
+        li->tv_sec = tm; li->tv_usec = 0;
 #endif
 }
 
-void
-login_set_ip4(struct logininfo *li,
-                      const struct sockaddr_in *sa_in4) {
-        memcpy((void *)&(li->hostaddr.sa_in4), (const void *)sa_in4,
-               sizeof(struct sockaddr_in));
-}
 
-#ifdef HAVE_IP6
+/* copy a sockaddr_* into our logininfo */
 void
-login_set_ip6(struct logininfo *li,
-                      const struct sockaddr_in6 *sa_in6) {
-        memcpy((void *)&(li->hostaddr.sa_in4), (const void *)sa_in6,
-               sizeof(struct sockaddr_in6));
+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);
 }
-#endif
 
-/*
- * record the entry
- */
+
+/**
+ ** login_write: Call low-level recording functions based on autoconf
+ ** results
+ **/
 
 int
-login_write (struct logininfo *li) {
-  
+login_write (struct logininfo *li)
+{
         if ((int)geteuid() != 0) {
           log("Attempt to write login records by non-root user (aborting)");
           return 1;
@@ -306,97 +372,75 @@ login_write (struct logininfo *li) {
         return 0;
 }
 
-int
-login_login (struct logininfo *li) {
-        li->type = LTYPE_LOGIN;
-        return login_write(li);
-}
 
-int
-login_logout(struct logininfo *li) {
-        li->type = LTYPE_LOGOUT;
-        return login_write(li);
-}
+/**
+ ** getlast_entry: Call low-level functions to retrieve the last login
+ **                time.
+ **/
 
+/* take the uid in li and return the last login time */
 int
-login_log_entry(struct logininfo *li) {
-        return login_write(li);
-}
-
-
-unsigned int
-login_getlasttime_name(const char *username) {
-        struct logininfo li;
-
-        memset(&li, '\0', sizeof(li));
-        login_set_username(&li, username);
-        if (getlast_entry(&li))
-                return li.tv_sec;
+getlast_entry(struct logininfo *li)
+{
+#ifdef USE_LASTLOG
+        if (lastlog_get_entry(li))
+                return 1;
         else
                 return 0;
-} /* login_getlasttime_name() */
-
-
-unsigned int
-login_getlasttime_uid(const int uid) {
-        struct logininfo li;
+#else
+        /* !USE_LASTLOG */
 
-        memset(&li, '\0', sizeof(li));
-        login_set_uid(&li, uid);
-        if (getlast_entry(&li))
-                return li.tv_sec;
+        /* Try to retrieve the last login time from wtmp */
+#  if defined(USE_WTMP) && (defined(HAVE_TIME_IN_UTMP) || defined(HAVE_TV_IN_UTMP))
+        /* retrieve last login time from utmp */
+        if (wtmp_get_entry(li))
+                return 1;
         else
                 return 0;
-} /* login_getlasttime_uid() */
+#  else
 
+        /* If wtmp isn't available, try wtmpx */
 
-struct logininfo *
-login_getlastentry_name(struct logininfo *li,
-                                          const char *username) {
-        login_set_username(li, username);
-        if (getlast_entry(li))
-                return li;
+#    if defined(USE_WTMPX) && (defined(HAVE_TIME_IN_UTMPX) || defined(HAVE_TV_IN_UTMPX))
+        /* retrieve last login time from utmpx */
+        if (wtmpx_get_entry(li))
+                return 1;
         else
                 return 0;
-} /* login_getlastentry_name() */
+#    else
 
-struct logininfo *
-login_getlastentry_uid(struct logininfo *li,
-                       const int uid) {
-        login_set_uid(li, uid);
-        if (getlast_entry(li))
-                return li;
-        else
-                return 0;
-} /* login_getlastentry_uid() */
+        /* Give up: No means of retrieving last login time */
+        return 0;
+#    endif
+#  endif
+#endif
+/* USE_LASTLOG */
+}
 
 
-/**
- ** 'line' string utility functions
- **/
 
 /*
- * process the 'line' string into three forms:
+ * '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
+ * 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 and is the same at login and
- * logout time, we're in good shape.
- *
- * NOTE: None of these calls actually allocate any memory -
- *       since their target is probably a structure, they don't
- *       need to.
+ * performed by one application - say, sshd - so as long as the choice
+ * uniquely identifies a terminal it's ok.
  */
 
 
-/* add the leading '/dev/' if it doesn't exist
- * make sure dst has enough space, if not just copy src (ugh) */
+/* 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, int dstsize) {
+line_fullname(char *dst, const char *src, int dstsize)
+{
         memset(dst, '\0', dstsize);
         if ((strncmp(src, "/dev/", 5) == 0) || (dstsize < (strlen(src) + 5)))
                 strlcpy(dst, src, dstsize);
@@ -407,50 +451,48 @@ line_fullname(char *dst, const char *src, int dstsize) {
         return dst;
 }
 
-/* strip the leading '/dev' if it exists, return dst */
+
+/* line_stripname(): strip the leading '/dev' if it exists, return dst */
 char *
-line_stripname(char *dst, const char *src, int dstsize) {
+line_stripname(char *dst, const char *src, int dstsize)
+{
         memset(dst, '\0', dstsize);
         if (strncmp(src, "/dev/", 5) == 0)
                 strlcpy(dst, &src[5], dstsize);
         else
                 strlcpy(dst, src, dstsize);
         return dst;
-} /* stripdev() */
+}
+
   
-/* return the abbreviated (usually four-character) form *
- * simple algorithm for making name:
- * - first character is 'L' (arbitrary - 'lib(L)ogin' :-) )
- * - remaining n characters are last n characters of line
- * This is good for up to 999 ptys, I hope that's enough...
- */
+/* 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, int dstsize) {
         memset(dst, '\0', dstsize);
-        dst[0]='L';
-        strlcpy(dst+1, &src[strlen(src)-(dstsize)], dstsize);
+        src += (strlen(src) - dstsize);
+        strncpy(dst, src, dstsize); /* note: _don't_ change this to strlcpy */
         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)
 
-#ifdef HAVE_UTMP_H
-#  include <utmp.h>
-#endif
-#ifdef USE_TIMEVAL
-#  include <sys/time.h>
-#else
-#  include <time.h>
-#endif
-
 /* build the utmp structure */
 void
-set_utmp_time(struct logininfo *li, struct utmp *ut) {
+set_utmp_time(struct logininfo *li, struct utmp *ut)
+{
 #ifdef HAVE_TV_IN_UTMP
         ut->ut_tv.tv_sec = li->tv_sec;
         ut->ut_tv.tv_usec = li->tv_usec;
@@ -461,17 +503,18 @@ set_utmp_time(struct logininfo *li, struct utmp *ut) {
 #endif
 }
 
+
 void
 construct_utmp(struct logininfo *li,
-                    struct utmp *ut) {
+                    struct utmp *ut)
+{
         memset(ut, '\0', sizeof(struct utmp));
-
 #ifdef HAVE_ID_IN_UTMP
         line_abbrevname(ut->ut_id, li->line, sizeof(ut->ut_id));
 #endif
 
 #ifdef HAVE_TYPE_IN_UTMP
-        /* this is done here to keep utmp constants out of login.h */
+        /* This is done here to keep utmp constants out of login.h */
         switch (li->type) {
         case LTYPE_LOGIN:
                 ut->ut_type = USER_PROCESS;
@@ -492,32 +535,30 @@ construct_utmp(struct logininfo *li,
         strlcpy(ut->ut_host, li->hostname, sizeof(ut->ut_host));
 #endif
 #ifdef HAVE_ADDR_IN_UTMP
-        /* !!! not supported yet (can't see its big use either) */
-#endif
-  
-} /* construct_utmp() */
+        /* 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 
+}
 
 #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)
 
-#ifdef HAVE_UTMPX_H
-#  include <utmpx.h>
-#endif
-#ifdef USE_TIMEVAL
-#  include <sys/time.h>
-#else
-#  include <time.h>
-#endif
-
 /* build the utmpx structure */
 void
-set_utmpx_time(struct logininfo *li, struct utmpx *utx) {
+set_utmpx_time(struct logininfo *li, struct utmpx *utx)
+{
 #ifdef HAVE_TV_IN_UTMPX
         utx->ut_tv.tv_sec = li->tv_sec;
         utx->ut_tv.tv_usec = li->tv_usec;
@@ -528,11 +569,11 @@ set_utmpx_time(struct logininfo *li, struct utmpx *utx) {
 #endif
 }
 
+
 void
-construct_utmpx(struct logininfo *li,
-                     struct utmpx *utx) {
+construct_utmpx(struct logininfo *li, struct utmpx *utx)
+{
         memset(utx, '\0', sizeof(struct utmpx));
-
         line_abbrevname(utx->ut_id, li->line, sizeof(utx->ut_id));
 
         /* this is done here to keep utmp constants out of loginrec.h */
@@ -544,7 +585,6 @@ construct_utmpx(struct logininfo *li,
                 utx->ut_type = DEAD_PROCESS;
                 break;
         }
-
         utx->ut_pid = li->pid;
         line_stripname(utx->ut_line, li->line, sizeof(utx->ut_line));
         strlcpy(utx->ut_name, li->username, sizeof(utx->ut_name));
@@ -553,13 +593,13 @@ construct_utmpx(struct logininfo *li,
         strlcpy(utx->ut_host, li->hostname, sizeof(utx->ut_host));
 #endif
 #ifdef HAVE_ADDR_IN_UTMPX
-        /* !!! not supported yet (some issues with types of addresses) */
+        /* FIXME: (ATL) not supported yet */
 #endif
 #ifdef HAVE_SYSLEN_IN_UTMPX  
         /* this is safe because of the extra nulls in logininfo */
         utx->ut_syslen = strlen(li->hostname);
 #endif
-} /* construct_utmpx() */
+}
 
 #endif
 /* USE_UTMPX || USE_WTMPX */
@@ -567,15 +607,13 @@ construct_utmpx(struct logininfo *li,
 
 
 /**
- ** utmp functions
+ ** Low-level utmp functions
  **/
 
 /* FIXME: (ATL) utmp_write_direct needs testing */
 
 #ifdef USE_UTMP
 
-#include <utmp.h>
-
 /* if we can, use pututline() etc. */
 #if !defined(DISABLE_PUTUTLINE) && defined(HAVE_SETUTENT) && \
     defined(HAVE_PUTUTLINE)
@@ -586,8 +624,8 @@ construct_utmpx(struct logininfo *li,
 /* 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) {
-
+utmp_write_library(struct logininfo *li, struct utmp *ut)
+{
         setutent();
         pututline(ut);
 
@@ -595,15 +633,15 @@ utmp_write_library(struct logininfo *li, struct utmp *ut) {
         endutent();
 #endif
         return 1;
-} /* utmp_write_library() */
+}
 
 #else
 
 /* write a utmp entry direct to the file */
-/* This code is a slightly modification of code in OpenBSD's login.c
- *  (in libutil) and so is subject to the OpenBSD Licensing terms. */
+/* This is a slightly modification of code in OpenBSD's login.c */
 static int
-utmp_write_direct(struct logininfo *li, struct utmp *ut) {
+utmp_write_direct(struct logininfo *li, struct utmp *ut)
+{
         struct utmp old_ut;
         register int fd;
         int tty;
@@ -633,17 +671,16 @@ utmp_write_direct(struct logininfo *li, struct utmp *ut) {
                 return 1;
         } else
                 return 0;
-} /* utmp_write_direct() */
-
+}
 #endif /* UTMP_USE_LIBRARY */
 
 
 static int
-utmp_perform_login(struct logininfo *li) {
+utmp_perform_login(struct logininfo *li)
+{
         struct utmp ut;
 
         construct_utmp(li, &ut);
-
 #ifdef UTMP_USE_LIBRARY
         if (!utmp_write_library(li, &ut)) {
           log("utmp_perform_login: utmp_write_library() failed");
@@ -656,11 +693,12 @@ utmp_perform_login(struct logininfo *li) {
         }
 #endif
         return 1;
-} /* utmp_perform_login() */
+}
 
 
 static int
-utmp_perform_logout(struct logininfo *li) {
+utmp_perform_logout(struct logininfo *li)
+{
         struct utmp ut;
 
         memset(&ut, '\0', sizeof(ut));
@@ -681,12 +719,12 @@ utmp_perform_logout(struct logininfo *li) {
 #endif
 
         return 1;
-} /* utmp_perform_logout() */
+}
 
 
 int
-utmp_write_entry(struct logininfo *li) {
-
+utmp_write_entry(struct logininfo *li)
+{
         switch(li->type) {
         case LTYPE_LOGIN:
                 return utmp_perform_login(li);
@@ -698,7 +736,7 @@ utmp_write_entry(struct logininfo *li) {
                 log("utmp_write_entry: invalid type field");
                 return 0;
         }
-} /* utmp_write_entry() */
+}
 
 
 #endif
@@ -706,14 +744,12 @@ utmp_write_entry(struct logininfo *li) {
 
 
 /**
- ** utmpx functions
+ ** Low-level utmpx functions
  **/
 
 /* not much point if we don't want utmpx entries */
 #ifdef USE_UTMPX
 
-#include <utmpx.h>
-
 /* if we have the wherewithall, use pututxline etc. */
 #if !defined(DISABLE_PUTUTXLINE) && defined(HAVE_SETUTXENT) \
     && defined(HAVE_PUTUTXLINE)
@@ -724,8 +760,8 @@ utmp_write_entry(struct logininfo *li) {
 /* 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) {
-
+utmpx_write_library(struct logininfo *li, struct utmpx *utx)
+{
         setutxent();
         pututxline(utx);
 
@@ -733,7 +769,7 @@ utmpx_write_library(struct logininfo *li, struct utmpx *utx) {
         endutxent();
 #endif
         return 1;
-} /* utmpx_write_library() */
+}
 
 #else
 /* UTMPX_USE_LIBRARY */
@@ -741,21 +777,21 @@ utmpx_write_library(struct logininfo *li, struct utmpx *utx) {
 
 /* write a utmp entry direct to the file */
 static int
-utmpx_write_direct(struct logininfo *li, struct utmpx *utx) {
-  
+utmpx_write_direct(struct logininfo *li, struct utmpx *utx)
+{  
         log("utmpx_write_direct: not implemented!");
         return 0;
- } /* utmpx_write_direct() */
+}
 
 #endif
 /* UTMPX_USE_LIBRARY */
 
 static int
-utmpx_perform_login(struct logininfo *li) {
+utmpx_perform_login(struct logininfo *li)
+{
         struct utmpx utx;
 
         construct_utmpx(li, &utx);
-
 #ifdef UTMPX_USE_LIBRARY
         if (!utmpx_write_library(li, &utx)) {
                 log("utmpx_perform_login: utmp_write_library() failed");
@@ -768,11 +804,12 @@ utmpx_perform_login(struct logininfo *li) {
         }
 #endif
         return 1;
-} /* utmpx_perform_login() */
+}
 
 
 static int
-utmpx_perform_logout(struct logininfo *li) {
+utmpx_perform_logout(struct logininfo *li)
+{
         struct utmpx utx;
 
         memset(&utx, '\0', sizeof(utx));
@@ -790,14 +827,13 @@ utmpx_perform_logout(struct logininfo *li) {
 #else
         utmpx_write_direct(li, &utx);
 #endif
-
         return 1;
-} /* utmpx_perform_logout() */
+}
 
 
 int
-utmpx_write_entry(struct logininfo *li) {
-
+utmpx_write_entry(struct logininfo *li)
+{
         switch(li->type) {
         case LTYPE_LOGIN:
                 return utmpx_perform_login(li);
@@ -807,7 +843,7 @@ utmpx_write_entry(struct logininfo *li) {
                 log("utmpx_write_entry: invalid type field");
                 return 0;
         }
-} /* utmpx_write_entry() */
+}
 
 
 #endif
@@ -815,18 +851,16 @@ utmpx_write_entry(struct logininfo *li) {
 
 
 /**
- ** wtmp functions
+ ** Low-level wtmp functions
  **/
 
 #ifdef USE_WTMP 
 
-# include <utmp.h>
-
 /* write a wtmp entry direct to the end of the file */
-/* This code is a slight modification of code in OpenBSD's logwtmp.c
- * (in libutil) and so is subject to the OpenBSD licensing terms */
+/* This is a slight modification of code in OpenBSD's logwtmp.c */
 static int
-wtmp_write(struct logininfo *li, struct utmp *ut) {
+wtmp_write(struct logininfo *li, struct utmp *ut)
+{
         struct stat buf;
         int fd, ret = 1;
 
@@ -835,8 +869,7 @@ wtmp_write(struct logininfo *li, struct utmp *ut) {
                     WTMP_FILE, strerror(errno));
                 return 0;
         }
-  
-        if (fstat(fd, &buf) == 0) 
+        if (fstat(fd, &buf) == 0) 
                 if (write(fd, (char *)ut, sizeof(struct utmp)) != 
                     sizeof(struct utmp)) {
                         ftruncate(fd, buf.st_size);
@@ -845,23 +878,22 @@ wtmp_write(struct logininfo *li, struct utmp *ut) {
                         ret = 0;
                 }
         (void)close(fd);
-
         return ret;
-} /* wtmp_write() */
-
+}
 
 
 static int
-wtmp_perform_login(struct logininfo *li) {
+wtmp_perform_login(struct logininfo *li){
         struct utmp ut;
 
         construct_utmp(li, &ut);
         return wtmp_write(li, &ut);
-} /* wtmp_perform_login() */
+}
 
 
 static int
-wtmp_perform_logout(struct logininfo *li) {
+wtmp_perform_logout(struct logininfo *li)
+{
         struct utmp ut;
 
         construct_utmp(li, &ut);
@@ -877,12 +909,12 @@ wtmp_perform_logout(struct logininfo *li) {
         memset(&(ut.ut_addr), '\0', sizeof(ut.ut_addr));
 #endif
         return wtmp_write(li, &ut);
-} /* wtmp_perform_logout() */
+}
 
 
 int
-wtmp_write_entry(struct logininfo *li) {
-
+wtmp_write_entry(struct logininfo *li)
+{
         switch(li->type) {
         case LTYPE_LOGIN:
                 return wtmp_perform_login(li);
@@ -892,12 +924,12 @@ wtmp_write_entry(struct logininfo *li) {
                 log("wtmp_write_entry: invalid type field");
                 return 0;
         }
-} /* wtmp_write_entry() */
-
+}
 
 
 int
-wtmp_get_entry(struct logininfo *li) {
+wtmp_get_entry(struct logininfo *li)
+{
         struct stat st;
         struct utmp ut;
         int fd;
@@ -907,14 +939,12 @@ wtmp_get_entry(struct logininfo *li) {
                     WTMP_FILE, strerror(errno));
                 return 0;
         }
-  
-        if (fstat(fd, &st) != 0) {
+        if (fstat(fd, &st) != 0) {
                 log("wtmp_get_entry: couldn't stat %s: %s",
                     WTMP_FILE, strerror(errno));
                 close(fd);
                 return 0;
         }
-
         (void)lseek(fd, (off_t)(0-sizeof(struct utmp)), SEEK_END);
 
         do {
@@ -924,7 +954,6 @@ wtmp_get_entry(struct logininfo *li) {
                         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 utmp */
                 if ( strncmp(li->username, ut.ut_user, 8) == 0 ) {
@@ -948,7 +977,7 @@ wtmp_get_entry(struct logininfo *li) {
         } while (li->tv_sec == 0);
       
         return 1;
-} /* wtmp_get_entry() */
+}
 
 
 #endif
@@ -956,18 +985,16 @@ wtmp_get_entry(struct logininfo *li) {
 
 
 /**
- ** wtmpx functions
+ ** Low-level wtmpx functions
  **/
 
 #ifdef USE_WTMPX
 
-# include <utmpx.h>
-
 /* write a wtmpx entry direct to the end of the file */
-/* This code is a slight modification of code in OpenBSD's logwtmp.c
- * (in libutil) and so is subject to the OpenBSD licensing terms */
+/* This is a slight modification of code in OpenBSD's logwtmp.c */
 static int
-wtmpx_write(struct logininfo *li, struct utmpx *utx) {
+wtmpx_write(struct logininfo *li, struct utmpx *utx)
+{
         struct stat buf;
         int fd, ret = 1;
 
@@ -988,21 +1015,22 @@ wtmpx_write(struct logininfo *li, struct utmpx *utx) {
         (void)close(fd);
 
         return ret;
-} /* wtmpx_write() */
-
+}
 
 
 static int
-wtmpx_perform_login(struct logininfo *li) {
+wtmpx_perform_login(struct logininfo *li)
+{
         struct utmpx utx;
 
         construct_utmpx(li, &utx);
         return wtmpx_write(li, &utx);
-} /* wtmpx_perform_login() */
+}
 
 
 static int
-wtmpx_perform_logout(struct logininfo *li) {
+wtmpx_perform_logout(struct logininfo *li)
+{
         struct utmpx utx;
 
         construct_utmpx(li, &utx);
@@ -1019,12 +1047,12 @@ wtmpx_perform_logout(struct logininfo *li) {
 #endif
         return wtmpx_write(li, &utx);
 
-} /* wtmpx_perform_logout() */
+}
 
 
 int
-wtmpx_write_entry(struct logininfo *li) {
-
+wtmpx_write_entry(struct logininfo *li)
+{
         switch(li->type) {
         case LTYPE_LOGIN:
                 return wtmpx_perform_login(li);
@@ -1034,12 +1062,12 @@ wtmpx_write_entry(struct logininfo *li) {
                 log("wtmpx_write_entry: invalid type field");
                 return 0;
         }
-} /* wtmpx_write_entry() */
-
+}
 
 
 int
-wtmpx_get_entry(struct logininfo *li) {
+wtmpx_get_entry(struct logininfo *li)
+{
         struct stat st;
         struct utmpx utx;
         int fd;
@@ -1049,14 +1077,12 @@ wtmpx_get_entry(struct logininfo *li) {
                     WTMPX_FILE, strerror(errno));
                 return 0;
         }
-  
-        if (fstat(fd, &st) != 0) {
+        if (fstat(fd, &st) != 0) {
                 log("wtmpx_get_entry: couldn't stat %s: %s",
                     WTMP_FILE, strerror(errno));
                 close(fd);
                 return 0;
         }
-
         (void)lseek(fd, (off_t)(0-sizeof(struct utmpx)), SEEK_END);
 
         do {
@@ -1066,7 +1092,6 @@ wtmpx_get_entry(struct logininfo *li) {
                         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 ( strncmp(li->username, utx.ut_user, 8) == 0 ) {
@@ -1089,8 +1114,7 @@ wtmpx_get_entry(struct logininfo *li) {
                 }
         } while (li->tv_sec == 0);
         return 1;
-} /* wtmpx_get_entry() */
-
+}
 
 
 #endif
@@ -1099,25 +1123,14 @@ wtmpx_get_entry(struct logininfo *li) {
 
 
 /**
- ** libutil login() functions
+ ** Low-level libutil login() functions
  **/
 
 #ifdef USE_LOGIN
 
-#ifdef HAVE_UTMP_H
-#  include <utmp.h>
-#endif
-#ifdef HAVE_UTIL_H
-#  include <util.h>
-#endif
-#ifdef USE_TIMEVAL
-#  include <sys/time.h>
-#else
-#  include <time.h>
-#endif
-
 static int
-syslogin_perform_login(struct logininfo *li) {
+syslogin_perform_login(struct logininfo *li)
+{
         struct utmp *ut;
 
         if (! (ut = (struct utmp *)malloc(sizeof(struct utmp)))) {
@@ -1128,11 +1141,12 @@ syslogin_perform_login(struct logininfo *li) {
         login(ut);
 
         return 1;
-} /* syslogin_perform_login() */
+}
 
-static int
-syslogin_perform_logout(struct logininfo *li) {
 
+static int
+syslogin_perform_logout(struct logininfo *li)
+{
 #ifdef HAVE_LOGOUT
         char line[8];
   
@@ -1150,13 +1164,12 @@ syslogin_perform_logout(struct logininfo *li) {
          * so they should all be there, but... */
 #endif
         return 1;
-} /* syslogin_perform_logout() */
-
+}
 
 
 int
-syslogin_write_entry(struct logininfo *li) {
-
+syslogin_write_entry(struct logininfo *li)
+{
         switch (li->type) {
         case LTYPE_LOGIN:
                 return syslogin_perform_login(li);
@@ -1166,7 +1179,7 @@ syslogin_write_entry(struct logininfo *li) {
                 log("syslogin_write_entry: Invalid type field");
                 return 0;
         }
-} /* utmp_write_entry() */
+}
 
 
 #endif
@@ -1176,23 +1189,14 @@ syslogin_write_entry(struct logininfo *li) {
 
 
 /**
- ** lastlog functions
+ ** Low-level lastlog functions
  **/
 
 #ifdef USE_LASTLOG
 
-#ifdef HAVE_LASTLOG_H
-# include <lastlog.h>
-#else
-# if !defined(USE_UTMP) && !defined(USE_WTMP)
-#  include <utmp.h>
-# endif
-#endif
-
-
 static void
-lastlog_construct(struct logininfo *li,
-                              struct lastlog *last) {
+lastlog_construct(struct logininfo *li, struct lastlog *last)
+{
         /* clear the structure */
         memset(last, '\0', sizeof(struct lastlog));
   
@@ -1200,7 +1204,7 @@ lastlog_construct(struct logininfo *li,
                              sizeof(last->ll_line));
         strlcpy(last->ll_host, li->hostname, sizeof(last->ll_host));
         last->ll_time = li->tv_sec;
-} /* lastlog_construct() */
+}
 
 
 #define LL_FILE 1
@@ -1208,7 +1212,8 @@ lastlog_construct(struct logininfo *li,
 #define LL_OTHER 3
 
 static int
-lastlog_filetype(char *filename) {
+lastlog_filetype(char *filename)
+{
         struct stat st;
 
         if ( stat(LASTLOG_FILE, &st) != 0) {
@@ -1216,20 +1221,19 @@ lastlog_filetype(char *filename) {
                     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;
-} /* lastlog_filetype() */
+}
 
 
 /* open the file (using filemode) and seek to the login entry */
 static int
-lastlog_openseek(struct logininfo *li, int *fd, int filemode) {
-
+lastlog_openseek(struct logininfo *li, int *fd, int filemode)
+{
         off_t offset;
         int type;
         char lastlog_file[1024];
@@ -1255,7 +1259,6 @@ lastlog_openseek(struct logininfo *li, int *fd, int filemode) {
                     lastlog_file, strerror(errno));
                 return 0;
         }
-
         /* find this uid's offset in the lastlog file */
         offset = (off_t) ( (long)li->uid * sizeof(struct lastlog));
 
@@ -1265,10 +1268,11 @@ lastlog_openseek(struct logininfo *li, int *fd, int filemode) {
                 return 0;
         }
         return 1;
-} /* lastlog_openseek() */
+}
 
 static int
-lastlog_perform_login(struct logininfo *li) {
+lastlog_perform_login(struct logininfo *li)
+{
         struct lastlog last;
         int fd;
 
@@ -1286,12 +1290,12 @@ lastlog_perform_login(struct logininfo *li) {
                 return 1;
         } else
                 return 0;
-} /* lastlog_perform_login() */
+}
 
 
 int
-lastlog_write_entry(struct logininfo *li) {
-
+lastlog_write_entry(struct logininfo *li)
+{
         switch(li->type) {
         case LTYPE_LOGIN:
                 return lastlog_perform_login(li);
@@ -1299,22 +1303,21 @@ lastlog_write_entry(struct logininfo *li) {
                 log("lastlog_write_entry: Invalid type field");
                 return 0;
         }
-} /* lastlog_write_entry() */
-
+}
 
 
 static void
-lastlog_populate_entry(struct logininfo *li,
-                                   struct lastlog *last) {
+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, sizeof(li->hostname));
         li->tv_sec = last->ll_time;
-} /* lastlog_populate_entry() */
-
+}
 
 
 int
-lastlog_get_entry(struct logininfo *li) {
+lastlog_get_entry(struct logininfo *li)
+{
         struct lastlog last;
         int fd;
 
@@ -1328,58 +1331,10 @@ lastlog_get_entry(struct logininfo *li) {
                         lastlog_populate_entry(li, &last);
                         return 1;
                 }
-
         } else
                 return 0;    
-} /* lastlog_get_entry() */
+}
 
 
 #endif
 /* USE_LASTLOG */
-
-
-/**
- ** lastlog retrieval functions
- **/
-
-/* take the uid in li and return the last login time */
-int
-getlast_entry(struct logininfo *li) {
-
-#ifdef USE_LASTLOG
-        if (lastlog_get_entry(li))
-                return 1;
-        else
-                return 0;
-#else
-        /* !USE_LASTLOG */
-        /* Try to retrieve the last login time from another source */
-
-#  if defined(USE_WTMP) && (defined(HAVE_TIME_IN_UTMP) || defined(HAVE_TV_IN_UTMP))
-
-        /* retrieve last login time from utmp */
-        if (wtmp_get_entry(li))
-                return 1;
-        else
-                return 0;
-
-#  else
-#    if defined(USE_WTMPX) && (defined(HAVE_TIME_IN_UTMPX) || defined(HAVE_TV_IN_UTMPX))
-
-        /* retrieve last login time from utmpx */
-        if (wtmpx_get_entry(li))
-                return 1;
-        else
-                return 0;
-
-#    else
-
-        /* no means of retrieving last login time */
-        return 0;
-#    endif
-#  endif
-
-#endif
-        /* USE_LASTLOG */
-
-}