<?php

/* $Id$ */
/*
	$RCSfile$
	
	Copyright (C) 2008 Scott Ullrich <sullrich@gmail.com>
	All rights reserved.
	
	Copyright (C) 2006  Fernando Lemos
	All rights reserved.

	This file was rewritten from scratch by Fernando Lemos but
	*MIGHT* contain code previously written by:

	Copyright (C) 2005 Peter Allgeyer <allgeyer_AT_web.de>
	All rights reserved.

	Copyright (C) 2004 Peter Curran (peter@closeconsultants.com).
	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 notices,
	   this list of conditions and the following disclaimer.

	2. Redistributions in binary form must reproduce the above copyright
	   notices, 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('config.inc');
require_once('pfsense-utils.inc');
require_once('util.inc');

$openvpn_prots = array( "UDP", "TCP");

$openvpn_auth_methods = array(
	'pki' => "Public Key Infrastructure",
	'shared_key' => "Pre Shared Key");

function openvpn_vpnid_used($vpnid) {
	global $config;

	if (is_array($config['openvpn']['openvpn-server']))
		foreach ($config['openvpn']['openvpn-server'] as $id => & $settings)
			if( $vpnid == $settings['vpnid'] )
				return true;

	if (is_array($config['openvpn']['openvpn-client']))
		foreach ($config['openvpn']['openvpn-client'] as $id => & $settings)
			if( $vpnid == $settings['vpnid'] )
				return true;

	return false;
}

function openvpn_vpnid_next() {

	$vpnid = 1;
	while(openvpn_vpnid_used($vpnid))
		$vpnid++;

	return $vpnid;
}

function openvpn_get_cipherlist() {

	$ciphers = array();
	$cipher_out = shell_exec('openvpn --show-ciphers | grep "default key" | awk \'{print $1, "(" $2 "-" $3 ")";}\'');
	$cipher_lines = explode("\n", trim($cipher_out));
	sort($cipher_lines);
	foreach ($cipher_lines as $line) {
		$words = explode(' ', $line);
		$ciphers[$words[0]] = "{$words[0]} {$words[1]}";
	}

	return $ciphers;
}

function openvpn_validate_host($value, $name) {
	$value = trim($value);
	if (empty($value) || !(is_domain($value) && is_ipaddr($value)))
		return "The field '$name' must contain a valid IP address or domain name.";
	return false;
}

function openvpn_validate_port($value, $name) {
	$value = trim($value);
	if (empty($value) || !(is_numeric($value) && ($value > 0) && ($value < 65535)))
		return "The field '$name' must contain a valid port, ranging from 0 to 65535.";
	return false;
}

function openvpn_validate_cidr($value, $name) {
	$value = trim($value);
	if (!empty($value)) {
		list($ip, $mask) = explode('/', $value);
		if (!is_ipaddr($ip) or !is_numeric($mask) or ($mask > 32) or ($mask < 0))
			return "The field '$name' must contain a valid CIDR range.";
	}
	return false;
}

function openvpn_add_dhcpopts(& $settings, & $conf) {

	if (!empty($settings['dns_domain'])) 
		$conf .= "push \"dhcp-option DOMAIN {$settings['dns_domain']}\"\n";

	if (!empty($settings['dns_server1']))
		$conf .= "push \"dhcp-option DNS {$settings['dns_server1']}\"\n";
	if (!empty($settings['dns_server2']))
		$conf .= "push \"dhcp-option DNS {$settings['dns_server2']}\"\n";
	if (!empty($settings['dns_server3']))
		$conf .= "push \"dhcp-option DNS {$settings['dns_server3']}\"\n";
	if (!empty($settings['dns_server4']))
		$conf .= "push \"dhcp-option DNS {$settings['dns_server4']}\"\n";

	if (!empty($settings['ntp_server1']))
		$conf .= "push \"dhcp-option NTP {$settings['dhcp_ntp']}\"\n";
	if (!empty($settings['ntp_server2']))
		$conf .= "push \"dhcp-option NTP {$settings['dhcp_ntp']}\"\n";

	if ($settings['netbios_enable']) {

  		if (!empty($settings['dhcp_nbttype']) && ($settings['dhcp_nbttype'] != 0))
 			$conf .= "push \"dhcp-option NBT {$settings['dhcp_nbttype']}\"\n";
    	if (!empty($settings['dhcp_nbtscope'])) 
			$conf .= "push \"dhcp-option NBS {$settings['dhcp_nbtscope']}\"\n";

		if (!empty($settings['wins_server1']))
			$conf .= "push \"dhcp-option WINS {$settings['wins_server1']}\"\n";
		if (!empty($settings['wins_server2']))
			$conf .= "push \"dhcp-option WINS {$settings['wins_server2']}\"\n";

		if (!empty($settings['nbdd_server1']))
			$conf .= "push \"dhcp-option NBDD {$settings['nbdd_server1']}\"\n";
	}

	if ($settings['gwredir']) 
		$conf .= "push \"redirect-gateway def1\"\n";
}

function openvpn_add_custom(& $settings, & $conf) {

	if ($settings['custom_options']) {

		$options = explode(';', $settings['custom_options']);

		if (is_array($options)) {
			foreach ($options as $option)
				$conf .= "$option\n";
		} else
			$conf .= "{$settings['custom_options']}\n";
	}
}

function openvpn_add_keyfile(& $data, & $conf, $mode_id, $directive) {
	global $g;

	$fpath = $g['varetc_path']."/openvpn/{$mode_id}.{$directive}";
	file_put_contents($fpath, base64_decode($data));
	chown($fpath, 'nobody');
	chgrp($fpath, 'nobody');

	$conf .= "{$directive} {$fpath}\n";
}

function openvpn_reconfigure($mode, $id) {
	global $g, $config;

	$settings = $config['openvpn']["openvpn-$mode"][$id];

	if (empty($settings))
		return;
	if ($settings['disable']) 
		return;

	/*
	 * NOTE: Deleting tap devices causes spontaneous reboots. Instead,
	 * we use a vpnid number which is allocated for a particular client
	 * or server configuration. ( see openvpn_vpnid_next() )
	 */

	$vpnid = $settings['vpnid'];
	$mode_id = $mode.$vpnid;
	$tunname = "tun{$vpnid}";

	if ($mode == "server")
		$devname = "ovpns{$vpnid}";
	else
		$devname = "ovpnc{$vpnid}";

	if (!file_exists("/dev/{$tunname}"))
		$tunname = exec("/sbin/ifconfig {$tunname} create");

	mwexec("/sbin/ifconfig {$tunname} name {$devname}");
	mwexec("/sbin/ifconfig {$devname} group openvpn");

	$pidfile = $g['varrun_path'] . "/openvpn_{$mode_id}.pid";
	$proto = ($settings['protocol'] == 'UDP' ? 'udp' : "tcp-{$mode}");
	$cipher = $settings['crypto'];

	$interface = $settings['interface'];
	if (!$interface)
		$interface = 'WAN';

	$iface = convert_friendly_interface_to_real_interface_name($interface);
	$lines = explode(' ', trim(shell_exec("ifconfig $iface | grep inet | grep -v inet6")));
	$iface_ip = $lines[1];

$conf .= <<<EOD
dev {$devname}
dev-type tun
dev-node /dev/{$tunname}
writepid $pidfile
#user nobody
#group nobody
daemon
keepalive 10 60
ping-timer-rem
persist-tun
persist-key
proto $proto
cipher $cipher
up /etc/rc.filter_configure
down /etc/rc.filter_configure
local {$iface_ip}

EOD;

	// Mode specific stuff

	if ($mode == 'server') {

		list($ip, $mask) = explode('/', $settings['tunnel_network']);
		$mask = gen_subnet_mask($mask);

		// Using a shared key or not dynamically assigning IPs to the clients
		if (($settings['auth_method'] == 'shared_key') || (!$settings['pool_enable'] == 'on')) {

			if ($settings['auth_method'] == 'pki')
				$conf .= "tls-server\n";

			$baselong = ip2long($ip) & ip2long($mask);
			$ip1 = long2ip($baselong + 1);
			$ip2 = long2ip($baselong + 2);
			$conf .= "ifconfig $ip1 $ip2\n";
		}
		// Using a PKI
		else if ($settings['auth_method'] == 'pki') {

			if ($settings['client2client'])
				$conf .= "client-to-client\n";

			$conf .= "server $ip $mask\n";
			$csc_dir = "{$g['varetc_path']}/openvpn_csc";
			$conf .= "client-config-dir $csc_dir\n";
		}

		// We can push routes
		if (!empty($settings['local_network'])) {

			list($ip, $mask) = explode('/', $settings['local_network']);
			$mask = gen_subnet_mask($mask);
			$conf .= "push \"route $ip $mask\"\n";
		}

		// The port we'll listen at
		$conf .= "lport {$settings['local_port']}\n";

		if (!empty($settings['maxclients'])) 
			$conf .= "max-clients {$settings['maxclients']}\n";

		openvpn_add_dhcpopts($settings, $conf);
	}

	if ($mode == 'client') {

		// The remote server
		$conf .= "remote {$settings['server_addr']} {$settings['server_port']}\n";

		if ($settings['auth_method'] == 'pki')
			$conf .= "client\n";

		// FIXME : This should be a gui option
		// The port we'll listen at
		if ($settings['local_port'])
			$conf .= "lport {$settings['local_port']}\n";
		else
			$conf .= "nobind\n";

		if (!empty($settings['use_shaper']))
			$conf .= "shaper {$settings['use_shaper']}\n";

		if (!empty($settings['tunnel_network'])) {

			// Configure the IPs according to the address pool
			list($ip, $mask) = explode('/', $settings['tunnel_network']);
			$mask = gen_subnet_mask($mask);
			$baselong = ip2long($ip) & ip2long($mask);
			$ip1 = long2ip($baselong + 1);
			$ip2 = long2ip($baselong + 2);
			$conf .= "ifconfig $ip2 $ip1\n";
		}

		if ($settings['proxy_addr']) {
			/* ;http-proxy-retry # retry on connection failures */
			$conf .= "http-proxy {$settings['proxy_addr']} {$settings['proxy_port']}\n";
		}
	}

	// Add the routes if they're set
	if (!empty($settings['remote_network'])) {
		list($ip, $mask) = explode('/', $settings['remote_network']);
		$mask = gen_subnet_mask($mask);
		$conf .= "route $ip $mask\n";
	}

	// Write the settings for the keys
	if ($settings['auth_method'] == 'shared_key')
		openvpn_add_keyfile($settings['shared_key'], $conf, $mode_id, "secret");

	if ($settings['auth_method'] == 'pki') {

		$ca = lookup_ca($settings['caref']);
		$cert = lookup_cert($settings['certref']);

		openvpn_add_keyfile($ca['crt'], $conf, $mode_id, "ca");
		openvpn_add_keyfile($cert['crt'], $conf, $mode_id, "cert");
		openvpn_add_keyfile($cert['prv'], $conf, $mode_id, "key");

		if ($mode == 'server') {
			$path_ovdh = $g['varetc_path']."/openvpn/dh-parameters";
			$conf .= "dh {$path_ovdh}\n";
		}

		if ($settings['crl'])
			openvpn_add_keyfile($settings['crl'], $conf, $mode_id, "crl-verify");
		if ($settings['tls']) 
			openvpn_add_keyfile($settings['tls'], $conf, $mode_id, "tls-auth");
	}

	if ($settings['compress'])
		$conf .= "comp-lzo\n";

	if ($settings['passtos'])
		$conf .= "passtos\n";

	if ($settings['resolve_retry'])
		$conf .= "resolv-retry infinite\n";

	if ($settings['dynamic_ip']) {
		$conf .= "persist-remote-ip\n";
		$conf .= "float\n";
	}

	openvpn_add_custom($settings, $conf);

	$fpath = $g['varetc_path']."/openvpn/{$mode_id}.conf";
	file_put_contents($fpath, $conf);
	chown($fpath, 'nobody');
	chgrp($fpath, 'nobody');
}

function openvpn_restart($mode, $id) {
	global $g, $config;

	$settings = $config['openvpn']["openvpn-$mode"][$id];
	$vpnid = $settings['vpnid'];
	$mode_id = $mode.$vpnid;

	$pidfile = $g['varrun_path']."/openvpn_{$mode_id}.pid";
	killbypid($pidfile);
	sleep(2);

	if ($settings['disable'])
		return;

	$fpath = $g['varetc_path']."/openvpn/{$mode_id}.conf";
	mwexec_bg("nohup openvpn --config {$fpath}");
	touch("{$g['tmp_path']}/filter_dirty");
}

function openvpn_delete($mode, $id) {
	global $g, $config;

	$settings = $config['openvpn']["openvpn-$mode"][$id];
	$vpnid = $settings['vpnid'];
	$mode_id = $mode.$vpnid;

	$ps = $g['varetc_path']."/openvpn_{$mode_id}.conf";
	$ps_id = `ps awux | grep $ps | awk '{ print \$2 }'`;
	killbypid($ps_id);
}

function openvpn_resync_csc($id) {
	global $g, $config;

	$settings = $config['openvpn']['openvpn-csc'][$id];
	$fpath = $g['varetc_path']."/openvpn_csc/".$settings['common_name'];

	if ($settings['disable']) {
		unlink_if_exists($fpath);
		return;
	}

	$conf = '';
	if ($settings['block'])
		$conf .= "disable\n";

	if ($settings['push_reset'])
		$conf .= "push-reset\n";

	if (!empty($settings['tunnel_network'])) {
		list($ip, $mask) = explode('/', $settings['tunnel_network']);
		$baselong = ip2long($ip) & gen_subnet_mask_long($mask);
		$ip1 = long2ip($baselong + 1);
		$ip2 = long2ip($baselong + 2);
		$conf .= "ifconfig-push {$ip1} {$ip2}\n";
	}

	openvpn_add_dhcpopts($settings, $conf);

	if ($settings['gwredir'])
		$conf .= "push \"redirect-gateway def1\"\n";

	openvpn_add_custom($settings, $conf);

	file_put_contents($fpath, $conf);
	chown($fpath, 'nobody');
	chgrp($fpath, 'nobody');
}

function openvpn_delete_csc($id) {
	global $g, $config;

	$settings = $config['openvpn']['openvpn-csc'][$id];
	$fpath = $g['varetc_path']."/openvpn_csc/".$settings['common_name'];
	unlink_if_exists($fpath);
}

// Resync the configuration and restart the VPN
function openvpn_resync($mode, $id) {
	openvpn_reconfigure($mode, $id);
	openvpn_restart($mode, $id);
}

// Resync and restart all VPNs
function openvpn_resync_all() {
	global $g, $config;

	$path_ovpn = $g['varetc_path']."/openvpn";
	safe_mkdir($path_ovpn);

	chown($path_ovpn, 'nobody');
	chgrp($path_ovpn, 'nobody');

	$path_ovdh = $g['varetc_path']."/openvpn/dh-parameters";
	if (!file_exists($path_ovdh)) {
		echo "Setting up OpenVPN environment ...\n";
		exec("/usr/bin/openssl dhparam -out {$path_ovdh} 1024");
	}

	$path_csc = $g['varetc_path']."/openvpn_csc";
	safe_mkdir($path_csc);

	chown($path_csc, 'nobody');
	chgrp($path_csc, 'nobody');

	if (is_array($config['openvpn']['openvpn-server']))
		foreach ($config['openvpn']['openvpn-server'] as $id => & $settings)
			openvpn_resync('server', $id);

	if (is_array($config['openvpn']['openvpn-client']))
		foreach ($config['openvpn']['openvpn-client'] as $id => & $settings)
			openvpn_resync('client', $id);

	if (is_array($config['openvpn']['openvpn-csc']))
		foreach ($config['openvpn']['openvpn-csc'] as $id => & $settings)
			openvpn_resync_csc($id);

	/* give speedy machines time to settle */
	sleep(5);

	/* reload the filter policy */
	filter_configure();
}

?>