* src/login.c: Added comments.

	* src/login.c: Close the user and group files before dropping root
	privileges.

diff --git a/ChangeLog b/ChangeLog
index 60777472900813004eb19f2a0f4d73b9ae590dad..d0b9981749729cfb0cad5b7c731daae6a42c8d45 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2009-04-20  Nicolas François  <nicolas.francois@centraliens.net>
+
+       * src/login.c: Added comments.
+       * src/login.c: Close the user and group files before dropping root
+       privileges.
+
 2009-04-20  Nicolas François  <nicolas.francois@centraliens.net>
 
        * src/login.c: We do not need to keep the old umask. Discard the

diff --git a/src/login.c b/src/login.c
index 503f05270288d531dde66a550f38019aa4163fcb..152992cebae8c170f11bb6ffaadfd0cf6f746fc4 100644 (file)
--- a/src/login.c
+++ b/src/login.c
@@ -2,7 +2,7 @@
  * Copyright (c) 1989 - 1994, Julianne Frances Haugh
  * Copyright (c) 1996 - 2001, Marek Michałkiewicz
  * Copyright (c) 2001 - 2006, Tomasz Kłoczko
- * Copyright (c) 2007 - 2008, Nicolas François
+ * Copyright (c) 2007 - 2009, Nicolas François
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -838,6 +838,10 @@ int main (int argc, char **argv)
                exit (1);
        }
 
+       /* This set up the process credential (group) and initialize the
+        * supplementary group access list.
+        * This has to be done before pam_setcred
+        */
        if (setup_groups (pwd) != 0) {
                exit (1);
        }
@@ -1156,10 +1160,24 @@ int main (int argc, char **argv)
                }
        }
 
-       /* We call set_groups() above because this clobbers pam_groups.so */
+
+       /*
+        * Close all the files so that unauthorized access won't occur.
+        */
+       endpwent ();            /* stop access to password file */
+       endgrent ();            /* stop access to group file */
+       endspent ();            /* stop access to shadow passwd file */
+#ifdef SHADOWGRP
+       endsgent ();            /* stop access to shadow group file */
+#endif
+
+       /* Drop root privileges */
 #ifndef USE_PAM
        if (setup_uid_gid (&pwent, is_console))
 #else
+       /* The group privileges were already dropped.
+        * See setup_groups() above.
+        */
        if (change_uid (&pwent))
 #endif
        {
@@ -1247,12 +1265,6 @@ int main (int argc, char **argv)
        (void) signal (SIGHUP, SIG_DFL);        /* added this.  --marekm */
        (void) signal (SIGINT, SIG_DFL);        /* default interrupt signal */
 
-       endpwent ();            /* stop access to password file */
-       endgrent ();            /* stop access to group file */
-       endspent ();            /* stop access to shadow passwd file */
-#ifdef SHADOWGRP
-       endsgent ();            /* stop access to shadow group file */
-#endif
        if (0 == pwent.pw_uid) {
                SYSLOG ((LOG_NOTICE, "ROOT LOGIN %s", fromhost));
        } else if (getdef_bool ("LOG_OK_LOGINS")) {