<?php
/*
  Copyright (C) 2008 Bill Marquette, Seth Mos
  Copyright (C) 2010 Ermal Luçi
  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.

	pfSense_BUILDER_BINARIES:	/sbin/route	/usr/local/sbin/apinger
	pfSense_MODULE:	routing

 */
require_once("config.inc");

/* Returns an array of default values used for apinger.conf */
function return_apinger_defaults() {
	return array(
		"latencylow" => "200",
		"latencyhigh" => "500",
		"losslow" => "10",
		"losshigh" => "20",
		"interval" => "1",
		"down" => "10");
	}

/*
 * Creates monitoring configuration file and
 * adds appropriate static routes.
 */
function setup_gateways_monitor() {
	global $config, $g;

	$gateways_arr = return_gateways_array();
	if (!is_array($gateways_arr)) {
		log_error("No gateways to monitor. Apinger will not be run.");
		killbypid("{$g['varrun_path']}/apinger.pid");
		@unlink("{$g['varrun_path']}/apinger.status");
		return;
	}

	$apinger_default = return_apinger_defaults();
	$apingerconfig = <<<EOD

# pfSense apinger configuration file. Automatically Generated!

## User and group the pinger should run as
user "root"
group "wheel"

## Mailer to use (default: "/usr/lib/sendmail -t")
#mailer "/var/qmail/bin/qmail-inject"

## Location of the pid-file (default: "/var/run/apinger.pid")
pid_file "{$g['varrun_path']}/apinger.pid"

## Format of timestamp (%s macro) (default: "%b %d %H:%M:%S")
#timestamp_format "%Y%m%d%H%M%S"

status {
	## File where the status information should be written to
	file "{$g['varrun_path']}/apinger.status"
	## Interval between file updates
	## when 0 or not set, file is written only when SIGUSR1 is received
	interval 5s
}

########################################
# RRDTool status gathering configuration
# Interval between RRD updates
rrd interval 60s;

## These parameters can be overridden in a specific alarm configuration
alarm default {
	command on "/usr/local/sbin/pfSctl -c 'service reload dyndns %T' -c 'service reload ipsecdns' -c 'service reload openvpn %T' -c 'filter reload' "
	command off "/usr/local/sbin/pfSctl -c 'service reload dyndns %T' -c 'service reload ipsecdns' -c 'service reload openvpn %T' -c 'filter reload' "
	combine 10s
}

## "Down" alarm definition.
## This alarm will be fired when target doesn't respond for 30 seconds.
alarm down "down" {
	time {$apinger_default['down']}s
}

## "Delay" alarm definition.
## This alarm will be fired when responses are delayed more than 200ms
## it will be canceled, when the delay drops below 100ms
alarm delay "delay" {
	delay_low {$apinger_default['latencylow']}ms
	delay_high {$apinger_default['latencyhigh']}ms
}

## "Loss" alarm definition.
## This alarm will be fired when packet loss goes over 20%
## it will be canceled, when the loss drops below 10%
alarm loss "loss" {
	percent_low {$apinger_default['losslow']}
	percent_high {$apinger_default['losshigh']}
}

target default {
	## How often the probe should be sent
	interval {$apinger_default['interval']}s

	## How many replies should be used to compute average delay
	## for controlling "delay" alarms
	avg_delay_samples 10

	## How many probes should be used to compute average loss
	avg_loss_samples 50

	## The delay (in samples) after which loss is computed
	## without this delays larger than interval would be treated as loss
	avg_loss_delay_samples 20

	## Names of the alarms that may be generated for the target
	alarms "down","delay","loss"

	## Location of the RRD
	#rrd file "{$g['vardb_path']}/rrd/apinger-%t.rrd"
}

EOD;

	$monitor_ips = array();
	foreach($gateways_arr as $name => $gateway) {
		/* Do not monitor if such was requested */
		if (isset($gateway['monitor_disable']))
			continue;
		if (empty($gateway['monitor']) || !is_ipaddr($gateway['monitor'])) {
			if (is_ipaddr($gateway['gateway']))
				$gateway['monitor'] = $gateway['gateway'];
			else /* No chance to get an ip to monitor skip target. */
				continue;
		}

		/* if the monitor address is already used before, skip */
		if(in_array($gateway['monitor'], $monitor_ips))
			continue;

		/* Interface ip is needed since apinger will bind a socket to it. */
		if (is_ipaddrv4($gateway['gateway'])) {
			$gwifip = find_interface_ip($gateway['interface'], true);
			if (!is_ipaddrv4($gwifip))
				continue; //Skip this target

			/*
			 * If the gateway is the same as the monitor we do not add a
			 * route as this will break the routing table.
			 * Add static routes for each gateway with their monitor IP
			 * not strictly necessary but is a added level of protection.
			 */
			if (is_ipaddrv4($gateway['gateway']) && $gateway['monitor'] != $gateway['gateway']) {
				log_error("Removing static route for monitor {$gateway['monitor']} and adding a new route through {$gateway['gateway']}");
				mwexec("/sbin/route change -host " . escapeshellarg($gateway['monitor']) .
					" " . escapeshellarg($gateway['gateway']), true);
			}
		} else if (is_ipaddrv6($gateway['gateway'])) {
			/* link locals really need a different src ip */
			if(is_linklocal($gateway['gateway'])) {
				$gwifip = find_interface_ipv6_ll($gateway['interface'], true);
			} else {
				$gwifip = find_interface_ipv6($gateway['interface'], true);
			}
			if (is_linklocal($gateway['monitor']) && !strstr($gateway['monitor'], '%'))
				$gateway['monitor'] .= "%{$gateway['interface']}";
			if (!is_ipaddrv6($gwifip))
				continue; //Skip this target

			/*
			 * If the gateway is the same as the monitor we do not add a
			 * route as this will break the routing table.
			 * Add static routes for each gateway with their monitor IP
			 * not strictly necessary but is a added level of protection.
			 */
			if (is_ipaddrv6($gateway['gateway']) && $gateway['monitor'] != $gateway['gateway']) {
				log_error("Removing static route for monitor {$gateway['monitor']} and adding a new route through {$gateway['gateway']}");
				mwexec("/sbin/route change -host -inet6 " . escapeshellarg($gateway['monitor']) .
					" " . escapeshellarg($gateway['gateway']), true);
			}
		} else
			continue;

		$monitor_ips[] = $gateway['monitor'];
		$apingercfg = "target \"{$gateway['monitor']}\" {\n";
		$apingercfg .= "	description \"{$name}\"\n";
		$apingercfg .= "	srcip \"{$gwifip}\"\n";
		if (!empty($gateway['interval']) && intval($gateway['interval']) > 1)
			$apingercfg .= "	interval " . intval($gateway['interval']) . "s\n";
		$alarms = "";
		$alarmscfg = "";
		$override = false;
		if (!empty($gateway['losslow'])) {
			$alarmscfg .= "alarm loss \"{$name}loss\" {\n";
			$alarmscfg .= "\tpercent_low {$gateway['losslow']}\n";
			$alarmscfg .= "\tpercent_high {$gateway['losshigh']}\n";
			$alarmscfg .= "}\n";
			$alarms .= "\"{$name}loss\"";
			$override = true;
		} else {
			if ($override == true)
				$alarms .= ",";
			$alarms .= "\"loss\"";
			$override = true;
		}
		if (!empty($gateway['latencylow'])) {
			$alarmscfg .= "alarm delay \"{$name}delay\" {\n";
			$alarmscfg .= "\tdelay_low {$gateway['latencylow']}ms\n";
			$alarmscfg .= "\tdelay_high {$gateway['latencyhigh']}ms\n";
			$alarmscfg .= "}\n";
			if ($override == true)
				$alarms .= ",";
			$alarms .= "\"{$name}delay\"";
			$override = true;
		} else {
			if ($override == true)
				$alarms .= ",";
			$alarms .= "\"delay\"";
			$override = true;
		}
		if (!empty($gateway['down'])) {
			$alarmscfg .= "alarm down \"{$name}down\" {\n";
			$alarmscfg .= "\ttime {$gateway['down']}s\n";
			$alarmscfg .= "}\n";
			if ($override == true)
				$alarms .= ",";
			$alarms .= "\"{$name}down\"";
			$override = true;
		} else {
			if ($override == true)
				$alarms .= ",";
			$alarms .= "\"down\"";
			$override = true;
		}
		if ($override == true)
			$apingercfg .= "\talarms override {$alarms};\n";

		$apingercfg .= "	rrd file \"{$g['vardb_path']}/rrd/{$gateway['name']}-quality.rrd\"\n";
		$apingercfg .= "}\n";
		$apingercfg .= "\n";

		$apingerconfig .= $alarmscfg;
		$apingerconfig .= $apingercfg;
	}
	@file_put_contents("{$g['varetc_path']}/apinger.conf", $apingerconfig);
	unset($apingerconfig);

	if (is_dir("{$g['tmp_path']}"))
		chmod("{$g['tmp_path']}", 01777);
	if (!is_dir("{$g['vardb_path']}/rrd"))
		mkdir("{$g['vardb_path']}/rrd", 0775);

	@chown("{$g['vardb_path']}/rrd", "nobody");

	if (isvalidpid("{$g['varrun_path']}/apinger.pid"))
		sigkillbypid("{$g['varrun_path']}/apinger.pid", "HUP");
	else {
		/* start a new apinger process */
		@unlink("{$g['varrun_path']}/apinger.status");
		sleep(1);
		mwexec_bg("/usr/local/sbin/apinger -c {$g['varetc_path']}/apinger.conf");
		sleep(1);
		sigkillbypid("{$g['varrun_path']}/apinger.pid", "USR1");
	}

	return 0;
}

/* return the status of the apinger targets as a array */
function return_gateways_status($byname = false) {
	global $config, $g;

	$apingerstatus = array();
	/* Always get the latest status from apinger */
	if (file_exists("{$g['varrun_path']}/apinger.pid"))
                sigkillbypid("{$g['varrun_path']}/apinger.pid", "USR1");
	if (file_exists("{$g['varrun_path']}/apinger.status")) {
		$apingerstatus = file("{$g['varrun_path']}/apinger.status");
	} else
		$apingerstatus = array();

	$status = array();
	foreach($apingerstatus as $line) {
		$info = explode("|", $line);
		if ($byname == false)
			$target = $info[0];
		else
			$target = $info[2];

		$status[$target] = array();
		$status[$target]['monitorip'] = $info[0];
		$status[$target]['srcip'] = $info[1];
		$status[$target]['name'] = $info[2];
		$status[$target]['lastcheck'] = $info[5] ? date('r', $info[5]) : date('r');
		$status[$target]['delay'] = empty($info[6]) ? "0ms" : round($info[6], 1) ."ms" ;
		$status[$target]['loss'] = empty($info[7]) ? "0.0%" : round($info[7], 1) . "%";
		$status[$target]['status'] = trim($info[8]);
	}

	/* tack on any gateways that have monitoring disabled
	 * or are down, which could cause gateway groups to fail */
	$gateways_arr = return_gateways_array();
	foreach($gateways_arr as $gwitem) {
		if(!isset($gwitem['monitor_disable']))
			continue;
		if(!is_ipaddr($gwitem['monitorip'])) {
			$realif = $gwitem['interface'];
			$tgtip = get_interface_gateway($realif);
			if (!is_ipaddr($tgtip))
				$tgtip = "none";
			$srcip = find_interface_ip($realif);
		} else {
			$tgtip = $gwitem['monitorip'];
			$srcip = find_interface_ip($realif);
		}
		if($byname == true)
			$target = $gwitem['name'];
		else
			$target = $tgtip;

		/* failsafe for down interfaces */
		if($target == "none") {
			$target = $gwitem['name'];
			$status[$target]['name'] = $gwitem['name'];
			$status[$target]['lastcheck'] = date('r');
			$status[$target]['delay'] = "0.0ms";
			$status[$target]['loss'] = "100.0%";
			$status[$target]['status'] = "down";
		} else {
			$status[$target]['monitorip'] = $tgtip;
			$status[$target]['srcip'] = $srcip;
			$status[$target]['name'] = $gwitem['name'];
			$status[$target]['lastcheck'] = date('r');
			$status[$target]['delay'] = "0.0ms";
			$status[$target]['loss'] = "0.0%";
			$status[$target]['status'] = "none";
		}
	}
	return($status);
}

/* Return all configured gateways on the system */
function return_gateways_array($disabled = false, $localhost = false, $inactive = false) {
	global $config, $g;

	$gateways_arr = array();

	$found_defaultv4 = 0;
	$found_defaultv6 = 0;

	// Ensure the interface cache is up to date first
	$interfaces = get_interface_arr(true);
	$interfaces_v4 = array();
	$interfaces_v6 = array();

	$i = -1;
	/* Process/add all the configured gateways. */
	if (is_array($config['gateways']['gateway_item'])) {
		foreach ($config['gateways']['gateway_item'] as $gateway) {
			/* Increment it here to do not skip items */
			$i++;

			if (empty($config['interfaces'][$gateway['interface']])) {
				if ($inactive === false)
					continue;
				else
					$gateway['inactive'] = true;
			}
			$wancfg = $config['interfaces'][$gateway['interface']];

			/* skip disabled interfaces */
			if ($disabled === false && (!isset($wancfg['enable']) || !isset($gateway['disabled'])))
				continue;

			/* if the gateway is dynamic and we can find the IPv4, Great! */
			if (empty($gateway['gateway']) || $gateway['gateway'] == "dynamic" || $gateway['gateway'] == "dynamic6") {
				if ($gateway['ipprotocol'] == "inet") {
					/* we know which interfaces is dynamic, this should be made a function */
					$gateway['ipprotocol'] = "inet";
					$gateway['gateway'] = get_interface_gateway($gateway['interface']);
					/* no IP address found, set to dynamic */
					if (!is_ipaddrv4($gateway['gateway']))
						$gateway['gateway'] = "dynamic";
					$gateway['dynamic'] = true;
				}

				/* if the gateway is dynamic6 and we can find the IPv6, Great! */
				else if ($gateway['ipprotocol'] == "inet6") {
					/* we know which interfaces is dynamic, this should be made a function, and for v6 too */
					$gateway['ipprotocol'] = "inet6";
					$gateway['gateway'] = get_interface_gateway_v6($gateway['interface']);
					/* no IPv6 address found, set to dynamic6 */
					if (!is_ipaddrv6($gateway['gateway']))
						$gateway['gateway'] = "dynamic6";
					$gateway['dynamic'] = true;
				}
			} else {
				/* getting this detection right is hard at this point because we still don't
				 * store the address family in the gateway item */
				if (is_ipaddrv4($gateway['gateway']))
					$gateway['ipprotocol'] = "inet";
				else if(is_ipaddrv6($gateway['gateway']))
					$gateway['ipprotocol'] = "inet6";
			}

			if (isset($gateway['monitor_disable']))
				$gateway['monitor_disable'] = true;
			else if (empty($gateway['monitor']))
				$gateway['monitor'] = $gateway['gateway'];

			$gateway['friendlyiface'] = $gateway['interface'];

			/* special treatment for tunnel interfaces */
			if ($gateway['ipprotocol'] == "inet6") {
				$gateway['interface'] = get_real_interface($gateway['interface'], "inet6", false, false);
				$interfaces_v6[$gateway['friendlyiface']] = $gateway['friendlyiface'];
			} else {
				$gateway['interface'] = get_real_interface($gateway['interface'], "all", false, false);
				$interfaces_v4[$gateway['friendlyiface']] = $gateway['friendlyiface'];
			}

			/* entry has a default flag, use it */
			if (isset($gateway['defaultgw'])) {
				if ($gateway['ipprotocol'] == "inet") {
					$gateway['defaultgw'] = true;
					$found_defaultv4 = 1;
				} else if ($gateway['ipprotocol'] == "inet6") {
					$gateway['defaultgw'] = true;
					$found_defaultv6 = 1;
				}
			}
			/* include the gateway index as the attribute */
			$gateway['attribute'] = $i;

			$gateways_arr[$gateway['name']] = $gateway;
		}
	}
	unset($gateway);

	/* Loop through all interfaces with a gateway and add it to a array */
	if ($disabled == false)
		$iflist = get_configured_interface_with_descr();
	else
		$iflist = get_configured_interface_with_descr(false, true);

	/* Process/add dynamic v4 gateways. */
	foreach($iflist as $ifname => $friendly ) {
		if(! interface_has_gateway($ifname))
			continue;

		if (empty($config['interfaces'][$ifname]))
			continue;

		$ifcfg = &$config['interfaces'][$ifname];
		if(!isset($ifcfg['enable']))
			continue;

		if(!empty($ifcfg['ipaddr']) && is_ipaddrv4($ifcfg['ipaddr']))
			continue;

		if (isset($interfaces_v4[$ifname]))
			continue;

		$ctype = "";
		switch($ifcfg['ipaddr']) {
			case "dhcp":
			case "pppoe":
			case "pptp":
			case "ppp":
				$ctype = strtoupper($ifcfg['ipaddr']);
				break;
			default:
				if (substr($ifcfg['if'], 0, 4) ==  "ovpn")
					$ctype = "VPNv4";
				break;
		}
		$ctype = "_". strtoupper($ctype);

		$gateway = array();
		$gateway['dynamic'] = false;
		$gateway['ipprotocol'] = "inet";
		$gateway['gateway'] = get_interface_gateway($ifname, $gateway['dynamic']);
		$gateway['interface'] = get_real_interface($ifname);
		$gateway['friendlyiface'] = $ifname;
		$gateway['name'] = "{$friendly}{$ctype}";
		$gateway['attribute'] = "system";

		if (($gateway['dynamic'] === "default") && ($found_defaultv4 == 0)) {
			$gateway['defaultgw'] = true;
			$gateway['dynamic'] = true;
			$found_defaultv4 = 1;
		}
		/* Loopback dummy for dynamic interfaces without a IP */
		if (!is_ipaddrv4($gateway['gateway']) && $gateway['dynamic'] == true)
			$gateway['gateway'] = "dynamic";

		/* automatically skip known static and dynamic gateways we have a array entry for */
		foreach($gateways_arr as $gateway_item) {
			if ((($ifname == $gateway_item['friendlyiface'] && $friendly == $gateway_item['name'])&& ($gateway['ipprotocol'] == $gateway_item['ipprotocol'])) ||
				($ifname == $gateway_item['friendlyiface'] && $gateway_item['dynamic'] == true) && ($gateway['ipprotocol'] == $gateway_item['ipprotocol']))
					continue 2;
		}

		if (is_ipaddrv4($gateway['gateway']))
			$gateway['monitor'] = $gateway['gateway'];

		$gateway['descr'] = "Interface {$friendly}{$ctype} Gateway";
		$gateways_arr[$gateway['name']] = $gateway;
	}
	unset($gateway);

	/* Process/add dynamic v6 gateways. */
	foreach($iflist as $ifname => $friendly ) {
		/* If the user has disabled IPv6, they probably don't want any IPv6 gateways. */
		if (!isset($config['system']['ipv6allow']))
			break;

		if(! interface_has_gatewayv6($ifname))
			continue;

		if (empty($config['interfaces'][$ifname]))
			continue;

		$ifcfg = &$config['interfaces'][$ifname];
		if(!isset($ifcfg['enable']))
			continue;

		if(!empty($ifcfg['ipaddrv6']) && is_ipaddrv6($ifcfg['ipaddrv6']))
			continue;

		if(isset($interfaces_v6[$ifname]))
			continue;

		$ctype = "";
		switch($ifcfg['ipaddrv6']) {
			case "slaac":
			case "dhcp6":
			case "6to4":
			case "6rd":
				$ctype = strtoupper($ifcfg['ipaddrv6']);
				break;
			default:
				if (substr($ifcfg['if'], 0, 4) ==  "ovpn")
					$ctype = "VPNv6";
				break;
		}
		$ctype = "_". strtoupper($ctype);

		$gateway = array();
		$gateway['dynamic'] = false;
		$gateway['ipprotocol'] = "inet6";
		$gateway['gateway'] = get_interface_gateway_v6($ifname, $gateway['dynamic']);
		$gateway['interface'] = get_real_interface($ifname, "inet6");
		switch($ifcfg['ipaddrv6']) {
			case "6rd":
			case "6to4":
				$gateway['dynamic'] = "default";
				break;
		}
		$gateway['friendlyiface'] = $ifname;
		$gateway['name'] = "{$friendly}{$ctype}";
		$gateway['attribute'] = "system";

		if (($gateway['dynamic'] === "default")  && ($found_defaultv6 == 0)) {
			$gateway['defaultgw'] = true;
			$gateway['dynamic'] = true;
			$found_defaultv6 = 1;
		}

		/* Loopback dummy for dynamic interfaces without a IP */
		if (!is_ipaddrv6($gateway['gateway']) && $gateway['dynamic'] == true)
			$gateway['gateway'] = "dynamic6";

		/* automatically skip known static and dynamic gateways we have a array entry for */
		foreach($gateways_arr as $gateway_item) {
			if ((($ifname == $gateway_item['friendlyiface'] && $friendly == $gateway_item['name']) && ($gateway['ipprotocol'] == $gateway_item['ipprotocol'])) ||
				($ifname == $gateway_item['friendlyiface'] && $gateway_item['dynamic'] == true) && ($gateway['ipprotocol'] == $gateway_item['ipprotocol']))
					continue 2;
		}

		if (is_ipaddrv6($gateway['gateway']))
			$gateway['monitor'] = $gateway['gateway'];

		$gateway['descr'] = "Interface {$friendly}{$ctype} Gateway";
		$gateways_arr[$gateway['name']] = $gateway;
	}
	unset($gateway);

	/* FIXME: Should this be enabled.
	 * Some interface like wan might be default but have no info recorded
	 * the config. */
	/* this is a fallback if all else fails and we want to get packets out @smos */
	if ($found_defaultv4 == 0 || $found_defaultv6 == 0) {
		foreach ($gateways_arr as &$gateway) {
			if (($gateway['friendlyiface'] == "wan") && ($found_defaultv4 == 0) && (!isset($gateway['ipprotocol']) || ($gateway['ipprotocol'] == "inet"))) {
				if (file_exists("{$g['tmp_path']}/{$gateway['interface']}_defaultgw")) {
					$gateway['defaultgw'] = true;
					$found_defaultv4 = 1;
				}
			}
			if (($gateway['friendlyiface'] == "wan") && ($found_defaultv6 == 0) && ($gateway['ipprotocol'] == "inet6")) {
				if (file_exists("{$g['tmp_path']}/{$gateway['interface']}_defaultgwv6")) {
					$gateway['defaultgw'] = true;
					$found_defaultv6 = 1;
				}
			}
		}
	}

	if($localhost === true) {
		/* attach localhost for Null routes */
		$gwlo4 = array();
		$gwlo4['name'] = "Null4";
		$gwlo4['interface'] = "lo0";
		$gwlo4['ipprotocol'] = "inet";
		$gwlo4['gateway'] = "127.0.0.1";
		$gwlo6 = array();
		$gwlo6['name'] = "Null6";
		$gwlo6['interface'] = "lo0";
		$gwlo6['ipprotocol'] = "inet6";
		$gwlo6['gateway'] = "::1";
		$gateways_arr['Null4'] = $gwlo4;
		$gateways_arr['Null6'] = $gwlo6;
	}
	return($gateways_arr);
}

function fixup_default_gateway($ipprotocol, $gateways_status, $gateways_arr) {
	global $config, $g;
	/*
	 * NOTE: The code below is meant to replace the default gateway when it goes down.
	 *	This facilitates services running on pfSense itself and are not handled by a PBR to continue working.
	 */
	$upgw = "";
	$dfltgwdown = false;
	$dfltgwfound = false;
	foreach ($gateways_arr as $gwname => $gwsttng) {
		if (($gwsttng['ipprotocol'] == $ipprotocol) && isset($gwsttng['defaultgw'])) {
			$dfltgwfound = true;
			$dfltgwname = $gwname;
			if (!isset($gwsttng['monitor_disable']) && stristr($gateways_status[$gwname]['status'], "down"))
				$dfltgwdown = true;
		}
		/* Keep a record of the last up gateway */
		/* XXX: Blacklist lan for now since it might cause issues to those who have a gateway set for it */
		if (empty($upgw) && ($gwsttng['ipprotocol'] == $ipprotocol) && (isset($gwsttng['monitor_disable']) || !stristr($gateways_status[$gwname]['status'], "down")) && $gwsttng[$gwname]['friendlyiface'] != "lan")
			$upgw = $gwname;
		if ($dfltgwdown == true && !empty($upgw))
			break;
	}
	if ($dfltgwfound == false) {
		$gwname = convert_friendly_interface_to_friendly_descr("wan");
		if (!empty($gateways_status[$gwname]) && stristr($gateways_status[$gwname]['status'], "down"))
			$dfltgwdown = true;
	}
	if ($dfltgwdown == true && !empty($upgw)) {
		if (preg_match("/dynamic/i", $gateways_arr[$upgw]['gateway']))
			$gateways_arr[$upgw]['gateway'] = get_interface_gateway($gateways_arr[$upgw]['friendlyiface']);
		if (is_ipaddr($gateways_arr[$upgw]['gateway'])) {
			log_error("Default gateway down setting {$upgw} as default!");
			if(is_ipaddrv6($gateways_arr[$upgw]['gateway'])) {
				$inetfamily = "-inet6";
			} else {
				$inetfamily = "-inet";
			}
			mwexec("/sbin/route change {$inetfamily} default {$gateways_arr[$upgw]['gateway']}");
		}
	} else {
		$defaultgw = trim(`/sbin/route -n get -{$ipprotocol} default | /usr/bin/grep gateway | /usr/bin/sed 's/gateway://g'`, " \n");
		if(is_ipaddrv6($gateways_arr[$dfltgwname]['gateway'])) {
			$inetfamily = "-inet6";
		} else {
			$inetfamily = "-inet";
		}
		if ($defaultgw != $gateways_arr[$dfltgwname]['gateway'])
			mwexec("/sbin/route change {$inetfamily} default {$gateways_arr[$dfltgwname]['gateway']}");
	}
}

/*
 * Return an array with all gateway groups with name as key
 * All gateway groups will be processed before returning the array.
 */
function return_gateway_groups_array() {
	global $config, $g;

	/* fetch the current gateways status */
	$gateways_status = return_gateways_status(true);
	$gateways_arr = return_gateways_array();
	$gateway_groups_array = array();

	if (isset($config['system']['gw_switch_default'])) {
		fixup_default_gateway("inet", $gateways_status, $gateways_arr);
		fixup_default_gateway("inet6", $gateways_status, $gateways_arr);
	}
	if (is_array($config['gateways']['gateway_group'])) {
		$carplist = get_configured_carp_interface_list();
		foreach ($config['gateways']['gateway_group'] as $group) {
			/* create array with group gateways members separated by tier */
			$tiers = array();
			$backupplan = array();
			$gwvip_arr = array();
			foreach ($group['item'] as $item) {
				list($gwname, $tier, $vipname) = explode("|", $item);

				if (is_ipaddr($carplist[$vipname])) {
					if (!is_array($gwvip_arr[$group['name']]))
						$gwvip_arr[$group['name']] = array();
					$gwvip_arr[$group['name']][$gwname] = $vipname;
				}

				/* Do it here rather than reiterating again the group in case no member is up. */
				if (!is_array($backupplan[$tier]))
					$backupplan[$tier] = array();
				$backupplan[$tier][] = $gwname;

				/* check if the gateway is available before adding it to the array */
				if (is_array($gateways_status[$gwname])) {
					$status = $gateways_status[$gwname];
					$gwdown = false;
					if (stristr($status['status'], "down")) {
						$msg = sprintf(gettext("MONITOR: %s is down, removing from routing group {$group['name']}"), $gwname);
						$gwdown = true;
					} else if (stristr($status['status'], "loss") && strstr($group['trigger'], "loss")) {
						/* packet loss */
						$msg = sprintf(gettext("MONITOR: %s has packet loss, removing from routing group {$group['name']}"), $gwname);
						$gwdown = true;
					} else if (stristr($status['status'], "delay") && strstr($group['trigger'] , "latency")) {
						/* high latency */
						$msg = sprintf(gettext("MONITOR: %s has high latency, removing from routing group {$group['name']}"), $gwname);
						$gwdown = true;
					}
					if ($gwdown == true) {
						log_error($msg);
						notify_via_growl($msg);
						notify_via_smtp($msg);
					} else {
						/* Online add member */
						if (!is_array($tiers[$tier]))
							$tiers[$tier] = array();
						$tiers[$tier][] = $gwname;
					}
				} else if (isset($gateways_arr[$gwname]['monitor_disable']))
					$tiers[$tier][] = $gwname;
			}
			$tiers_count = count($tiers);
			if ($tiers_count == 0) {
				/* Oh dear, we have no members! Engage Plan B */
				if (!$g['booting']) {
					$msg = gettext("Gateways status could not be determined, considering all as up/active. (Group: {$group['name']})");
					log_error($msg);
					notify_via_growl($msg);
					//notify_via_smtp($msg);
				}
				$tiers = $backupplan;
			}
			/* sort the tiers array by the tier key */
			ksort($tiers);

			/* we do not really foreach the tiers as we stop after the first tier */
			foreach ($tiers as $tieridx => $tier) {
				/* process all gateways in this tier */
				foreach ($tier as $member) {
					/* determine interface gateway */
					if (isset($gateways_arr[$member])) {
						$gateway = $gateways_arr[$member];
						$int = $gateway['interface'];
						$gatewayip = "";
						if(is_ipaddr($gateway['gateway']))
							$gatewayip = $gateway['gateway'];
						else if (!empty($int))
							$gatewayip = get_interface_gateway($gateway['friendlyiface']);

						if (!empty($int) && is_ipaddr($gatewayip)) {
							$groupmember = array();
							$groupmember['int']  = $int;
							$groupmember['gwip']  = $gatewayip;
							$groupmember['weight']  = isset($gateway['weight']) ? $gateway['weight'] : 1;
							if (is_array($gwvip_arr[$group['name']])&& !empty($gwvip_arr[$group['name']][$member]))
								$groupmember['vip'] = $gwvip_arr[$group['name']][$member];
							$gateway_groups_array[$group['name']]['ipprotocol'] = $gateway['ipprotocol'];
							$gateway_groups_array[$group['name']][] = $groupmember;
						}
					}
				}
				/* we should have the 1st available tier now, exit stage left */
				if (count($gateway_groups_array[$group['name']]) > 0)
					break;
				else
					log_error("GATEWAYS: Group {$group['name']} did not have any gateways up on tier {$tieridx}!");
			}
		}
	}

	return ($gateway_groups_array);
}

/* Update DHCP WAN Interface ip address in gateway group item */
function dhclient_update_gateway_groups_defaultroute($interface = "wan") {
	global $config, $g;
	foreach($config['gateways']['gateway_item'] as & $gw) {
		if($gw['interface'] == $interface) {
			$current_gw = get_interface_gateway($interface);
			if($gw['gateway'] <> $current_gw) {
				$gw['gateway'] = $current_gw;
				$changed = true;
			}
		}
	}
	if($changed && $current_gw)
		write_config(sprintf(gettext('Updating gateway group gateway for %1$s - new gateway is %2$s'), $interfac, $current_gw));
}

function lookup_gateway_ip_by_name($name) {

	$gateways_arr = return_gateways_array(false, true);
	foreach ($gateways_arr as $gname => $gw) {
		if ($gw['name'] === $name || $gname === $name)
			return $gw['gateway'];
	}

	return false;
}

function lookup_gateway_monitor_ip_by_name($name) {

	$gateways_arr = return_gateways_array(false, true);
	if (!empty($gateways_arr[$name])) {
		$gateway = $gateways_arr[$name];
		if(!is_ipaddr($gateway['monitor']))
			return $gateway['gateway'];

		return $gateway['monitor'];
	}

	return (false);
}

function lookup_gateway_interface_by_name($name) {

	$gateways_arr = return_gateways_array(false, true);
	if (!empty($gateways_arr[$name])) {
		$interfacegw = $gateways_arr[$name]['friendlyiface'];
		return ($interfacegw);
	}

	return (false);
}

function get_interface_gateway($interface, &$dynamic = false) {
	global $config, $g;

	$gw = NULL;

	$gwcfg = $config['interfaces'][$interface];
	if (!empty($gwcfg['gateway']) && is_array($config['gateways']['gateway_item'])) {
		foreach($config['gateways']['gateway_item'] as $gateway) {
			if(($gateway['name'] == $gwcfg['gateway']) && (is_ipaddrv4($gateway['gateway']))) {
				$gw = $gateway['gateway'];
				break;
			}
		}
	}

	// for dynamic interfaces we handle them through the $interface_router file.
	if (!is_ipaddrv4($gw) && !is_ipaddrv4($gwcfg['ipaddr'])) {
		$realif = get_real_interface($interface);
		if (file_exists("{$g['tmp_path']}/{$realif}_router")) {
				$gw = trim(file_get_contents("{$g['tmp_path']}/{$realif}_router"), " \n");
			$dynamic = true;
		}
		if (file_exists("{$g['tmp_path']}/{$realif}_defaultgw"))
			$dynamic = "default";

	}

	/* return gateway */
	return ($gw);
}

function get_interface_gateway_v6($interface, &$dynamic = false) {
	global $config, $g;

	$gw = NULL;
	$gwcfg = $config['interfaces'][$interface];
	if (!empty($gwcfg['gatewayv6']) && is_array($config['gateways']['gateway_item'])) {
		foreach($config['gateways']['gateway_item'] as $gateway) {
			if(($gateway['name'] == $gwcfg['gatewayv6']) && (is_ipaddrv6($gateway['gateway']))) {
				$gw = $gateway['gateway'];
				break;
			}
		}
	}

	// for dynamic interfaces we handle them through the $interface_router file.
	if (!is_ipaddrv6($gw) && !is_ipaddrv6($gwcfg['ipaddrv6'])) {
			$realif = get_real_interface($interface);
			if (file_exists("{$g['tmp_path']}/{$realif}_routerv6")) {
				$gw = trim(file_get_contents("{$g['tmp_path']}/{$realif}_routerv6"), " \n");
				$dynamic = true;
			}
			if (file_exists("{$g['tmp_path']}/{$realif}_defaultgwv6"))
				$dynamic = "default";

	}
	/* return gateway */
	return ($gw);
}

/* Check a IP address against a gateway IP or name
 * to verify it's address family */
function validate_address_family($ipaddr, $gwname) {
	$v4ip = false;
	$v6ip = false;
	$v4gw = false;
	$v6gw = false;

	if(is_ipaddrv4($ipaddr))
		$v4ip = true;
	if(is_ipaddrv6($ipaddr))
		$v6ip = true;
	if(is_ipaddrv4($gwname))
		$v4gw = true;
	if(is_ipaddrv6($gwname))
		$v6gw = true;

	if($v4ip && $v4gw)
		return true;
	if($v6ip && $v6gw)
		return true;

	/* still no match, carry on, lookup gateways */
	if(is_ipaddrv4(lookup_gateway_ip_by_name($gwname)))
		$v4gw = true;
	if(is_ipaddrv6(lookup_gateway_ip_by_name($gwname)))
		$v6gw = true;

	$gw_array = return_gateways_array();
	if(is_array($gw_array[$gwname])) {
		switch($gw_array[$gwname]['ipprotocol']) {
			case "inet":
				$v4gw = true;
				break;
			case "inet6":
				$v6gw = true;
				break;
		}
	}

	if($v4ip && $v4gw)
		return true;
	if($v6ip && $v6gw)
		return true;

	return false;
}

/* check if a interface is part of a gateway group */
function interface_gateway_group_member($interface) {
	global $config;

	if (is_array($config['gateways']['gateway_group']))
		$groups = $config['gateways']['gateway_group'];
	else
		return false;

	$gateways_arr = return_gateways_array(false, true);
	foreach($groups as $group) {
		if(is_array($group['item'])) {
			foreach($group['item'] as $item) {
				$elements = explode("|", $item);
				$gwname = $elements[0];
				if ($interface == $gateways_arr[$gwname]['interface']) {
					unset($gateways_arr);
					return true;
				}
			}
		}
	}
	unset($gateways_arr);

	return false;
}

function gateway_is_gwgroup_member($name) {
	global $config;

	if (is_array($config['gateways']['gateway_group']))
		$groups = $config['gateways']['gateway_group'];
	else
		return false;

	$members = array();
	foreach($groups as $group) {
		if (is_array($group['item'])) {
			foreach($group['item'] as $item) {
				$elements = explode("|", $item);
				$gwname = $elements[0];
				if ($name == $elements[0])
					$members[] = $group['name'];
			}
		}
	}

	return $members;
}
?>