services: add OpenDNS filtering feature

Adapted the the GUI layout and rewrote the curl probing in PHP
while at it.  Many thanks for the initial code donation and idea!

Donated by: gastbox.ch

src/etc/inc/priv.defs.inc

@@ -854,6 +854,12 @@ $priv_list['page-services-dnsforwarder-edithost']['descr'] = gettext("Allow acce
 $priv_list['page-services-dnsforwarder-edithost']['match'] = array();
 $priv_list['page-services-dnsforwarder-edithost']['match'][] = "services_dnsmasq_edit.php*";
 
+$priv_list['page-services-opendns'] = array();
+$priv_list['page-services-opendns']['name'] = gettext("WebCfg - Services: DNS Filter");
+$priv_list['page-services-opendns']['descr'] = gettext("Allow access to the 'Services: DNS Filter' page.");
+$priv_list['page-services-opendns']['match'] = array();
+$priv_list['page-services-opendns']['match'][] = "services_opendns.php*";
+
 $priv_list['page-services-dnsresolver'] = array();
 $priv_list['page-services-dnsresolver']['name'] = gettext("WebCfg - Services: DNS Resolver page");
 $priv_list['page-services-dnsresolver']['descr'] = gettext("Allow access to the 'Services: DNS Resolver' page.");

src/opnsense/mvc/app/models/OPNsense/Base/Menu/Menu.xml

@@ -83,6 +83,7 @@
         <DHCPv6ServerRA VisibleName="DHCPv6 Server/RA" url="/services_dhcpv6.php">
             <RouterAdvertisement url="/services_router_advertisements.php"/>
         </DHCPv6ServerRA>
+        <DNSFilter VisibleName="DNS Filter" url="/services_opendns.php"/>
         <DNSForwarder VisibleName="DNS Forwarder" url="/services_dnsmasq.php"/>
         <DNSResolver VisibleName="DNS Resolver" url="/services_unbound.php">
             <Advanced url="/services_unbound_advanced.php/"/>

src/opnsense/mvc/app/models/OPNsense/Core/ACL_Legacy_Page_Map.txt

@@ -135,6 +135,7 @@ page-services-dhcpv6relay=services_dhcpv6_relay.php*
 page-services-dnsforwarder=services_dnsmasq.php*
 page-services-dnsforwarder-editdomainoverride=services_dnsmasq_domainoverride_edit.php*
 page-services-dnsforwarder-edithost=services_dnsmasq_edit.php*
+page-services-opendns=services_opendns.php*
 page-services-dnsresolver=services_unbound.php*
 page-services-dnsresolver-advanced=services_unbound_advanced.php*
 page-services-dnsresolver-acls=services_unbound_acls.php*

src/www/fbegin.inc

@@ -162,6 +162,7 @@ $firewall_menu = msort($firewall_menu,0);
 // Services
 $services_menu = array();
 $services_menu[] = array(gettext("Captive Portal"), "/services_captiveportal.php");
+$services_menu[] = array(gettext("DNS Filter"), "/services_opendns.php");
 $services_menu[] = array(gettext("DNS Forwarder"), "/services_dnsmasq.php");
 $services_menu[] = array(gettext("DNS Resolver"), "/services_unbound.php");
 $services_menu[] = array(gettext("DHCP Relay"), "/services_dhcp_relay.php");

src/www/services_opendns.php

+<?php
+
+/*
+	Copyright (c) 2015 Franco Fichtner <franco@opnsense.org>
+	Copyright (c) 2008 Tellnet AG
+	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.
+*/
+
+require_once 'guiconfig.inc';
+
+if (!is_array($config['opendns'])) {
+	$config['opendns'] = array();
+}
+
+$pconfig['enable'] = isset($config['opendns']['enable']);
+$pconfig['username'] = $config['opendns']['username'];
+$pconfig['password'] = $config['opendns']['password'];
+$pconfig['host'] = $config['opendns']['host'];
+
+if ($_POST) {
+	unset($input_errors);
+	$pconfig = $_POST;
+
+	/* input validation */
+	$reqdfields = array();
+	$reqdfieldsn = array();
+	if ($_POST['enable']) {
+		$reqdfields = array_merge($reqdfields, explode(" ", "host username password"));
+		$reqdfieldsn = array_merge($reqdfieldsn, explode(",", "Network,Username,Password"));
+	}
+	do_input_validation($_POST, $reqdfields, $reqdfieldsn, $input_errors);
+
+	if (($_POST['host'] && !is_domain($_POST['host']))) {
+		$input_errors[] = 'The host name contains invalid characters.';
+	}
+	if (($_POST['username'] && empty($_POST['username']))) {
+		$input_errors[] = 'The username cannot be empty.';
+	}
+
+	if ($_POST['test']) {
+		$ch = curl_init();
+		curl_setopt($ch, CURLOPT_URL, sprintf( 'https://updates.opendns.com/nic/update?hostname=%s', $pconfig['host']));
+		curl_setopt($ch, CURLOPT_USERPWD, sprintf('%s:%s', $pconfig['username'], $pconfig['password']));
+		curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
+		$output = curl_exec($ch);
+		curl_close($ch);
+		$test_results = explode("\r\n", $output);
+	} elseif (!$input_errors) {
+		$refresh = $pconfig['enable'] != $config['opendns']['enable'];
+		$config['opendns']['enable'] = $_POST['enable'] ? true : false;
+		$config['opendns']['username'] = $_POST['username'];
+		$config['opendns']['password'] = $_POST['password'];
+		$config['opendns']['host'] = $_POST['host'];
+		if ($refresh) {
+			if ($config['opendns']['enable']) {
+				unset($config['system']['dnsserver']);
+				$config['system']['dnsserver'][] = '208.67.222.222';
+				$config['system']['dnsserver'][] = '208.67.220.220';
+				$config['system']['dnsallowoverride'] = false;
+			} else {
+				unset($config['system']['dnsserver']);
+				$config['system']['dnsserver'][] = '';
+				$config['system']['dnsallowoverride'] = true;
+			}
+		}
+		write_config('OpenDNS filter configuration change');
+		if ($refresh) {
+			$retval = system_resolvconf_generate();
+			$savemsg = get_std_save_message($retval);
+		}
+	}
+}
+
+$pgtitle = array('Services', 'DNS Filter');
+
+include 'head.inc';
+
+?>
+
+<body>
+
+<?php include 'fbegin.inc'; ?>
+
+<section class="page-content-main">
+	<div class="container-fluid">
+
+	<div class="row">
+		<?php
+			if ($input_errors) {
+				print_input_errors($input_errors);
+			}
+			if ($savemsg) {
+				print_info_box($savemsg);
+			}
+		?>
+		<section class="col-xs-12">
+
+		<div class="content-box table-responsive">
+
+			<form action="services_opendns.php" method="post">
+				<table width="100%" border="0" cellpadding="6" cellspacing="0" summary="main area" class="table table-striped">
+					<thead>
+						<tr>
+							<th colspan="2" valign="top" class="listtopic"><?=gettext('OpenDNS Setup'); ?></th>
+						</tr>
+					</thead>
+					<tbody>
+						<tr>
+							<td width="22%" valign="top" class="vncellreq"><?=gettext('Enable'); ?></td>
+							<td width="78%" class="vtable">
+								<input name="enable" type="checkbox" id="enable" value="yes" <?php if ($pconfig['enable']) { echo 'checked="checked"'; } ?>" />
+								<strong><?=gettext('Filter DNS requests using OpenDNS'); ?></strong>
+								<br />
+								<br />
+								<span class="vexpl">
+									<?=gettext(sprintf(
+										'Enabling the OpenDNS service will overwrite DNS servers configured ' .
+										'via the General Setup page as well as ignore any DNS servers learned ' .
+										'by DHCP/PPP on WAN and use the DNS servers from %s instead.',
+										'<a href="http://www.opendns.com" target="_blank">OpenDNS.com</a>'
+									)); ?>
+								</span>
+							</td>
+						</tr>
+						<tr>
+							<td width="22%" valign="top" class="vncell"><?=gettext('Username'); ?></td>
+							<td width="78%" class="vtable">
+								<input name="username" type="text" id="username" size="20" value="<?=htmlspecialchars($pconfig['username']);?>" />
+								<br />
+								<span class="vexpl">
+									<?=gettext(
+										'Signon Username to log into your OpenDNS dashboard. ' .
+										'It is used to automatically update the IP address of ' .
+										'the registered network.'
+									); ?>
+								</span>
+							</td>
+						</tr>
+						<tr>
+							<td width="22%" valign="top" class="vncell"><?=gettext('Password'); ?></td>
+							<td width="78%" class="vtable">
+								<input name="password" type="password" id="password" size="20" value="<?=htmlspecialchars($pconfig['password']);?>" />
+							</td>
+						</tr>
+						<tr>
+							<td width="22%" valign="top" class="vncell"><?=gettext('Network'); ?></td>
+							<td width="78%" class="vtable">
+							<input name="host" type="text" id="host" size="30" value="<?=htmlspecialchars($pconfig['host']);?>" />
+								<br />
+								<span class="vexpl">
+									<?=gettext(sprintf(
+										'Enter the network name configured on the %s under ' .
+										'\'Manage your networks\'. Used to update the node\'s ' .
+										'IP address whenever the WAN interface changes its IP address.',
+										'<a href="https://www.opendns.com/dashboard/networks/" target="_blank">' .
+										gettext('Networks Dashboard of OpenDNS') .'</a>'
+									)); ?>
+								</span>
+							</td>
+						</tr>
+						<?php if (is_array($test_results)): ?>
+						<tr>
+							<td width="22%" valign="top"><?=gettext('Test result');?></td>
+							<td width="78%">
+							<?php
+								foreach ($test_results as $result) {
+									if (!strlen($result)) {
+										continue;
+									}
+
+									echo sprintf(
+										'<span class="glyphicon glyphicon-%s"></span> %s<br />',
+										strpos($result, 'good') === 0 ? 'ok text-success' : 'remove text-danger',
+										$result
+									);
+								}
+							?>
+							</td>
+						</tr>
+						<?php endif; ?>
+						<tr>
+							<td width="22%" valign="top">&nbsp;</td>
+							<td width="78%">
+								<input name="submit" type="submit" class="btn btn-primary" value="<?=gettext('Save');?>" />
+								<input name="test" type="submit" class="btn btn-primary" value="<?=gettext('Test/Update');?>" />
+							</td>
+						</tr>
+					</tbody>
+				</table>
+			</form>
+		</div>
+		</section>
+	</div>
+	</div>
+</section>
+
+<?php include 'foot.inc'; ?>