Minor re-work of OpenVPN configuration. Use operational modes to determine

what configuration options are appropriate. The operational mode dictates
the authentication method. They are defines as follows ...

Peer to Peer ( SSL/TLS )
Peer to Peer ( Shared Key )
Remote Access ( SSL/TLS )
Remote Access ( User Auth )
Remote Access ( SSL/TLS + User Auth )

Some of these modes allow for user authentication using passwords. We now
use the etc/inc/openvpn.auth-user.php file to facilitate this by checking
the username and password supplied by OpenVPN against our centralized user
database.

The Server and Client user interfaces have also been updated to support
TLS packet authentication. This is an additional security option that is
optional.

1 files changed, 79 insertions, 0 deletions

diff --git a/etc/inc/openvpn.auth-user.php b/etc/inc/openvpn.auth-user.php
new file mode 100755
index 0000000..275f54d
--- /dev/null
+++ b/etc/inc/openvpn.auth-user.php
@@ -0,0 +1,79 @@
+#!/usr/local/bin/php -f
+<?php
+/* $Id$ */
+/*
+    openvpn.auth-user.php
+
+    Copyright (C) 2008 Shrew Soft Inc
+    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.
+*/
+
+/*
+ * OpenVPN calls this script to authenticate a user
+ * based on a username and password. We lookup these
+ * in our config.xml file and check the credentials.
+ */
+
+require_once("config.inc");
+
+function & lookup_user($name) {
+	global $config;
+
+	foreach($config['system']['user'] as & $userent)
+		if ($userent['name'] == $name)
+			return $userent;
+}
+
+/* setup syslog logging */
+openlog("openvpn", LOG_ODELAY, LOG_AUTH);
+
+/* read data from environment */
+$username = getenv("username");
+$password = getenv("password");
+
+if (!$username || !$password) {
+	syslog(LOG_ERROR, "invalid user authentication environment");
+	exit(-1);
+}
+
+/* lookup user object by name */
+$user =& lookup_user($username);
+
+if (!$user) {
+	syslog(LOG_WARNING, "user {$username} is unknown");
+	exit(-2);
+}
+
+/* authenticate the user */
+$password = crypt($password, $user['password']);
+
+if ($password != $user['password']) {
+	syslog(LOG_WARNING, "user {$username} supplied an invalid password\n");
+	exit(-3);
+}
+
+syslog(LOG_WARNING, "user {$username} authenticated\n");
+exit(0);
+
+?>