1 files changed, 62 insertions, 0 deletions
diff --git a/pam_script_ses_close b/pam_script_ses_close
new file mode 100755
index 0000000..a59664c
--- /dev/null
+++ b/pam_script_ses_close
@@ -0,0 +1,62 @@
+#! /bin/bash
+# Copyright 2017 Cumulus Networks, Inc.  All rights reserved
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+
+# This script is invoked via pam_script.so for session close, to
+# clean up the mapping setup on session open.   The info is used
+# in the libnss_mapuser getpwuid() entry point.
+
+# auid is currently unused, but must match the uid of the mapped_user
+# in the libnss_mapuser database for this to be valid
+
+# For this to work, pam_loginuid.so must be used, so both the
+# loginuid and the sessionid are unique values > 0
+
+dbdir=/run/mapuser
+mkdir -p $dbdir
+
+read sess < /proc/$$/sessionid
+read auid < /proc/$$/loginuid
+
+# never map root user, or when loginuid isn't set, or when
+# we aren't doing mapping (env variable not set)
+if [ "$auid" -eq 0 ]; then exit 0; fi
+
+# for debugging, if needed
+# logger -t mapuser $0 called with $PAM_USER pid=$$ session="$sess" auid="$auid"
+
+if [ "$sess" -le 0 ] ; then
+	logger -t $0 sessionid not set, no mapuser cleanup for \
+	   PID $$ user $PAM_USER
+	exit 0 # never trigger an error
+fi
+
+file=$dbdir/$sess
+[ -e $file ] &&  {
+   IFS='=
+' read tag fauid <<< $(grep '^auid=' $file)
+   IFS='=
+' read tag fsess <<< $(grep '^session=' $file)
+   # If info doesn't match, report it, but clean up anyway.
+   [ "$auid" != "$fauid" -o "$sess" != "$fsess" ] &&
+     logger -t $0 "Session $sess mismatch auid $auid,$fauid session $sess,$fsess"
+
+   rm -f $file
+   }
+
+# always succeed, this should not cause sessions shutdown errors
+exit 0