(filter) cleanup unused alias table, closes https://github.com/opnsense/core/issues/903

(cherry picked from commit 0a89f824)

src/opnsense/scripts/filter/kill_table.py

+#!/usr/local/bin/python2.7
+
+"""
+    Copyright (c) 2016 Ad Schellevis
+    All rights reserved.
+
+    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 ``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.
+
+    --------------------------------------------------------------------------------------
+    drop an existing pf alias table
+"""
+import tempfile
+import subprocess
+import os
+import sys
+import ujson
+
+if __name__ == '__main__':
+    with tempfile.NamedTemporaryFile() as output_stream:
+        subprocess.call(['/sbin/pfctl', '-sT'], stdout=output_stream, stderr=open(os.devnull, 'wb'))
+        output_stream.seek(0)
+        tables = list()
+        for line in output_stream.read().strip().split('\n'):
+            tables.append(line.strip())
+        # only try to remove alias if it exists
+        if len(sys.argv) > 1 and sys.argv[1] in tables:
+            # cleanup related alias file
+            if os.path.isfile('/var/db/aliastables/%s.txt' % sys.argv[1]):
+                os.remove('/var/db/aliastables/%s.txt' % sys.argv[1])
+            subprocess.call(['/sbin/pfctl', '-t', sys.argv[1], '-T', 'kill'], stdout=open(os.devnull, 'wb'), stderr=open(os.devnull, 'wb'))
+            # all good, exit 0
+            sys.exit(0)
+
+# not found (or other issue)
+sys.exit(-1)

src/opnsense/service/conf/actions.d/actions_filter.conf

@@ -69,3 +69,9 @@ command:/usr/local/opnsense/scripts/filter/pfinfo.py
 parameters: %s
 type:script_output
 message:request pf diagnostic information
+
+[kill.table]
+command:/usr/local/opnsense/scripts/filter/kill_table.py
+parameters: %s
+type:script
+message:kill pf table ( %s )

src/www/firewall_aliases.php

@@ -139,6 +139,7 @@ if ($_SERVER['REQUEST_METHOD'] === 'POST') {
             if($is_alias_referenced) {
                 $savemsg = sprintf(gettext("Cannot delete alias. Currently in use by %s"), $referenced_by);
             } else {
+                configd_run("filter kill table {$alias_name}");
                 unset($a_aliases[$_POST['id']]);
                 if (write_config()) {
                     filter_configure();