- Merged bsd-login ttyslot and AIX utmp patch from Gert Doering

   <gd@hilb1.medat.de>

1 files changed, 82 insertions, 17 deletions

diff --git a/bsd-login.c b/bsd-login.c
index eccb29ee4..910f9ff9f 100644
--- a/bsd-login.c
+++ b/bsd-login.c
@@ -1,3 +1,7 @@
+/*
+ * This file has been modified from the original OpenBSD version 
+ */
+
 /*      $OpenBSD: login.c,v 1.5 1998/07/13 02:11:12 millert Exp $       */
 /*
  * Copyright (c) 1988, 1993
@@ -35,6 +39,8 @@
 #include "config.h"
 #ifndef HAVE_LOGIN
 
+#include <errno.h>
+
 #if defined(LIBC_SCCS) && !defined(lint)
 /* from: static char sccsid[] = "@(#)login.c    8.1 (Berkeley) 6/4/93"; */
 static char *rcsid = "$OpenBSD: login.c,v 1.5 1998/07/13 02:11:12 millert Exp $";
@@ -54,6 +60,40 @@ static char *rcsid = "$OpenBSD: login.c,v 1.5 1998/07/13 02:11:12 millert Exp $"
 #include <stdio.h>
 #include <string.h>
 
+/*
+ * find first matching slot in utmp, or "-1" for none
+ *
+ * algorithm: for USER_PROCESS, check tty name
+ *            for DEAD_PROCESS, check PID and tty name
+ *
+ */
+int find_tty_slot( utp )
+struct utmp * utp;
+{
+        int t = 0;
+        struct utmp * u;
+
+        setutent();
+
+        while((u = getutent()) != NULL) {
+                if (utp->ut_type == USER_PROCESS &&
+                    (strncmp(utp->ut_line, u->ut_line, sizeof(utp->ut_line)) == 0)) {
+                        endutent();
+                        return(t);
+                }
+
+                if ((utp->ut_type == DEAD_PROCESS) && (utp->ut_pid == u->ut_pid) &&
+                    (strncmp(utp->ut_line, u->ut_line, sizeof(utp->ut_line)) == 0 )) {
+                        endutent();
+                        return(t);
+                }
+                t++;
+        }
+
+        endutent();
+        return(-1);
+}
+
 #if defined(HAVE_UTMPX_H) && defined(USE_UTMPX)
 void
 login(utp,utx)
@@ -74,32 +114,57 @@ login(utp)
         register int fd;
         int tty;
 
-        tty = ttyslot();
-        if (tty > 0 && (fd = open(_PATH_UTMP, O_RDWR|O_CREAT, 0644)) >= 0) {
+        /* can't use ttyslot here, as that will not work for logout
+         * (record_logout() is called from the master sshd, which does
+         * not have the correct tty on stdin/out, so ttyslot will return
+         * "-1" or (worse) a wrong number
+         */
+        tty = find_tty_slot(utp);
 
+        fd = open(_PATH_UTMP, O_RDWR|O_CREAT, 0644);
+        if (fd == -1) {
+                log("Couldn't open %s: %s", _PATH_UTMP, strerror(errno));
+        } else {
+                /* If no tty was found... */
+                if (tty == -1) {
+                        /* ... append it to utmp on login */
+                        if (utp->ut_type == USER_PROCESS) {
+                                if ((fd = open(_PATH_UTMP, O_WRONLY|O_APPEND, 0)) >= 0) {
+                                        (void)write(fd, utp, sizeof(struct utmp));
+                                        (void)close(fd);
+                                }
+                        } else {
+                                /* Shouldn't get to here unless somthing happened to utmp */
+                                /* Between login and logout */
+                                log("No tty slot found at logout");
+                        }
+                } else {
+                        /* Otherwise, tty was found - update at its location */
 #if defined(HAVE_HOST_IN_UTMP)
 # ifndef UT_LINESIZE
 #  define UT_LINESIZE (sizeof(old_ut.ut_line))
 #  define UT_NAMESIZE (sizeof(old_ut.ut_name))
 #  define UT_HOSTSIZE (sizeof(old_ut.ut_host))
 # endif
-                (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 (read(fd, &old_ut, sizeof(struct utmp)) ==
-                    sizeof(struct utmp) && utp->ut_host[0] == '\0' &&
-                    old_ut.ut_host[0] != '\0' &&
-                    strncmp(old_ut.ut_line, utp->ut_line, UT_LINESIZE) == 0 &&
-                    strncmp(old_ut.ut_name, utp->ut_name, UT_NAMESIZE) == 0)
-                        (void)memcpy(utp->ut_host, old_ut.ut_host, UT_HOSTSIZE);
+                        (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 (read(fd, &old_ut, sizeof(struct utmp)) ==
+                         sizeof(struct utmp) && utp->ut_host[0] == '\0' &&
+                         old_ut.ut_host[0] != '\0' &&
+                         strncmp(old_ut.ut_line, utp->ut_line, UT_LINESIZE) == 0 &&
+                         strncmp(old_ut.ut_name, utp->ut_name, UT_NAMESIZE) == 0)
+                                (void)memcpy(utp->ut_host, old_ut.ut_host, UT_HOSTSIZE);
 #endif /* defined(HAVE_HOST_IN_UTMP) */
-                (void)lseek(fd, (off_t)(tty * sizeof(struct utmp)), SEEK_SET);
-                (void)write(fd, utp, sizeof(struct utmp));
-                (void)close(fd);
+                        (void)lseek(fd, (off_t)(tty * sizeof(struct utmp)), SEEK_SET);
+                        (void)write(fd, utp, sizeof(struct utmp));
+                        (void)close(fd);
+                }
         }
+
         if ((fd = open(_PATH_WTMP, O_WRONLY|O_APPEND, 0)) >= 0) {
                 (void)write(fd, utp, sizeof(struct utmp));
                 (void)close(fd);