Add interface tracking support. With this it is now possible for dynamic IPv6 interfaces to setup the corresponding lan interface for RA.

DHCP6 with prefix delegation to follow later for automatic daisychaining.

4 files changed, 353 insertions, 171 deletions

diff --git a/etc/inc/interfaces.inc b/etc/inc/interfaces.inc
index 429290a..b28c2da 100644
--- a/etc/inc/interfaces.inc
+++ b/etc/inc/interfaces.inc
@@ -1123,6 +1123,7 @@ function interface_bring_down($interface = "wan", $destroy = false) {
 		}
 		break;
 	case "6rd":
+		$realif = "srd0";
 		if(does_interface_exist("$realif")) {
 			mwexec("/sbin/ifconfig " . escapeshellarg($realif) . " delete", true);
 			if ($destroy == true)
@@ -1130,6 +1131,7 @@ function interface_bring_down($interface = "wan", $destroy = false) {
 		}		
 		break;
 	case "6to4":
+		$realif = "stf0";
 		if(does_interface_exist("$realif")) {
 			mwexec("/sbin/ifconfig " . escapeshellarg($realif) . " delete", true);
 			if ($destroy == true)
@@ -1164,7 +1166,7 @@ function interface_bring_down($interface = "wan", $destroy = false) {
 	}
 
 	if ($destroy == true) {
-		if (preg_match("/^vip|^tun|^ovpn|^gif|^gre|^lagg|^bridge|vlan/i", $realif))
+		if (preg_match("/^vip|^tun|^ovpn|^gif|^gre|^lagg|^bridge|vlan|^stf|^srd/i", $realif))
 			pfSense_interface_destroy($realif);
 	}	
 
@@ -2881,6 +2883,9 @@ function interface_configure($interface = "wan", $reloadall = false, $linkupeven
 		case '6to4':
 			interface_6to4_configure($interface);
 			break;
+		case 'track6':
+			interface_track6_configure($interface);
+			break;
 		default:
 			if (is_ipaddr($wancfg['ipaddrv6']) && $wancfg['subnetv6'] <> "") {
 				pfSense_interface_setaddress($realif, "{$wancfg['ipaddrv6']}/{$wancfg['subnetv6']}");
@@ -2959,7 +2964,157 @@ function interface_carpdev_dhcp_configure($interface = "wan") {
 	return 0;
 }
 
-function interface_6rd_configure($interface = "wan"){
+function interface_track6_configure($interface = "lan") {
+	global $config, $g;
+	$iflist = get_configured_interface_with_descr(false, true);
+
+	$wancfg = $config['interfaces'][$interface];
+	$wanif = $wancfg['if'];
+	if (empty($wancfg))
+		$wancfg = array();
+
+	$wanif = get_real_interface($interface);
+	
+	/* If the interface is not configured via another, exit */
+	if(!$wancfg['track6-interface'] <> "") {
+		return(false);
+	}
+	log_error("Interface {$interface} configured via {$wancfg['track6-interface']}  type {$config['interfaces'][$wancfg['track6-interface']]['ipaddrv6']}");
+
+	
+	switch($config['interfaces'][$wancfg['track6-interface']]['ipaddrv6']) {
+		case "6to4":
+			interface_track6_6to4_configure($interface);
+			break;
+		case "6rd":
+			interface_track6_6rd_configure($interface);
+			break;
+		case "dhcp6":
+			interface_track6_dhcp6_configure($interface);
+			break;
+		default:
+			log_error("Interface {$interface} configured via {$wancfg['track6-interface']} but unknown type {$config['interfaces'][$wancfg['track6-interface']]['ipaddrv6']}");
+			break;
+	}
+	return 0;
+}
+
+
+function interface_track6_6rd_configure($interface = "lan") {
+	global $config, $g;
+	$iflist = get_configured_interface_with_descr(false, true);
+
+	$lancfg = $config['interfaces'][$interface];
+	$lanif = $lancfg['if'];
+	if (empty($lancfg))
+		$lancfg = array();
+
+	$lanif = get_real_interface($interface);
+	
+	/* If the interface is not configured via another, exit */
+	if(!$lancfg['track6-interface'] <> "") {
+		return(false);
+	}
+	if(!is_numeric($lancfg['track6-prefix-id']))
+		$lancfg['track6-prefix-id'] = 0;
+	
+	$wancfg = $config['interfaces'][$lancfg['track6-interface']];
+	$wanif = $wancfg['if'];
+	if (empty($wancfg))
+		$wancfg = array();
+	
+	$ip4address = find_interface_ip($wanif);
+	if((!is_ipaddrv4($ip4address)) || (is_private_ip($ip4address))) {
+		log_error("The interface IPv4 '{$ip4address}' address on interface '{$wanif}' is not public, not configuring 6RD tunnel");
+		return false;
+	}
+	$hexwanv4 = return_hex_ipv4($ip4address);
+	
+	/* create the long prefix notation for math, save the prefix length */
+	$rd6prefix = explode("/", $wancfg['prefix-6rd']);
+	$rd6prefixlen = $rd6prefix[1];
+	$rd6prefix = Net_IPv6::uncompress($rd6prefix[0]);
+
+	/* binary presentation of the prefix for all 128 bits. */
+	$rd6lanbin = convert_ipv6_to_128bit($rd6prefix);
+	
+	/* just save the left prefix length bits */
+	$rd6lanbin = substr($rd6lanbin, 0, $rd6prefixlen);
+	/* add the v4 address, offset n bits from the left */
+	$rd6lanbin .= substr(sprintf("%032b", hexdec($hexwanv4)), (0 + $wancfg['prefix-6rd-v4plen']), 32);
+
+	/* add the custom prefix id, max 32bits long? (64 bits - (prefixlen + (32 - v4plen)) */
+	/* 64 - (37 + (32 - 17)) = 8 == /52 */
+	$restbits = 64 - ($rd6prefixlen + (32 - $wancfg['prefix-6rd-v4plen']));
+	// echo "64 - (prefixlen {$rd6prefixlen} + v4len (32 - {$wancfg['prefix-6rd-v4plen']})) = {$restbits} \n";
+	$rd6lanbin .= substr(sprintf("%032b", str_pad($lancfg['track6-prefix-id'], 32, "0", STR_PAD_LEFT)), (32 - $restbits), 32);
+	/* fill the rest out with zeros */
+	$rd6lanbin = str_pad($rd6lanbin, 128, "0", STR_PAD_RIGHT);;
+
+	/* convert the 128 bits for the lan address back into a valid IPv6 address */ 
+	$rd6lan = convert_128bit_to_ipv6($rd6lanbin) ."1";
+	
+	log_error("rd6 {$interface} with ipv6 address {$rd6lan} based on {$lancfg['track6-interface']} ipv4 {$ip4address}");
+	mwexec("/sbin/ifconfig {$lanif} inet6 {$rd6lan} prefixlen 64");
+	return 0;
+}
+
+function interface_track6_6to4_configure($interface = "lan") {
+	global $config, $g;
+	$iflist = get_configured_interface_with_descr(false, true);
+
+	$lancfg = $config['interfaces'][$interface];
+	$lanif = $lancfg['if'];
+	if (empty($lancfg))
+		$lancfg = array();
+
+	$lanif = get_real_interface($interface);
+	
+	/* If the interface is not configured via another, exit */
+	if(!$lancfg['track6-interface'] <> "") {
+		return(false);
+	}
+	if(!is_numeric($lancfg['track6-prefix-id']))
+		$lancfg['track6-prefix-id'] = 0;
+	
+	$wancfg = $config['interfaces'][$lancfg['track6-interface']];
+	$wanif = $wancfg['if'];
+	if (empty($wancfg))
+		$wancfg = array();
+	
+	$ip4address = find_interface_ip($wanif);
+	if((!is_ipaddrv4($ip4address)) || (is_private_ip($ip4address))) {
+		log_error("The interface IPv4 '{$ip4address}' address on interface '{$wanif}' is not public, not configuring 6RD tunnel");
+		return false;
+	}
+	$hexwanv4 = return_hex_ipv4($ip4address);
+	
+	/* create the long prefix notation for math, save the prefix length */
+	$sixto4prefix = "2002::";
+	$sixto4prefixlen = 16;
+	$sixto4prefix = Net_IPv6::uncompress($sixto4prefix);
+
+	/* binary presentation of the prefix for all 128 bits. */
+	$sixto4lanbin = convert_ipv6_to_128bit($sixto4prefix);
+	
+	/* just save the left prefix length bits */
+	$sixto4lanbin = substr($sixto4lanbin, 0, $sixto4prefixlen);
+	/* add the v4 address */
+	$sixto4lanbin .= sprintf("%032b", hexdec($hexwanv4));
+	/* add the custom prefix id */
+	$sixto4lanbin .= sprintf("%016b", $lancfg['track6-prefix-id']);
+	/* fill the rest out with zeros */
+	$sixto4lanbin = str_pad($sixto4lanbin, 128, "0", STR_PAD_RIGHT);;
+	
+	/* convert the 128 bits for the lan address back into a valid IPv6 address */ 
+	$sixto4lan = convert_128bit_to_ipv6($sixto4lanbin) ."1";
+	
+	log_error("sixto4 {$interface} with ipv6 address {$sixto4lan} based on {$lancfg['track6-interface']} ipv4 {$ip4address}");
+	mwexec("/sbin/ifconfig {$lanif} inet6 {$sixto4lan} prefixlen 64");
+	return 0;
+}
+
+function interface_6rd_configure($interface = "wan") {
 	global $config, $g;
 	$iflist = get_configured_interface_with_descr(false, true);
 
@@ -2978,88 +3133,42 @@ function interface_6rd_configure($interface = "wan"){
 		log_error("The interface IPv4 '{$ip4address}' address on interface '{$wanif}' is not public, not configuring 6RD tunnel");
 		return false;
 	}
+	$hexwanv4 = return_hex_ipv4($ip4address);
 	
 	if(!is_numeric($wancfg['prefix-6rd-v4plen']))
-		$v4prefixlen = 0;
-	else
-		$v4prefixlen = $wancfg['prefix-6rd-v4plen'];	
+		$wancfg['prefix-6rd-v4plen'] = 0;
 
 	/* create the long prefix notation for math, save the prefix length */
 	$rd6prefix = explode("/", $wancfg['prefix-6rd']);
 	$rd6prefixlen = $rd6prefix[1];
 	$rd6prefix = Net_IPv6::uncompress($rd6prefix[0]);
-	$rd6arr = explode(":", $rd6prefix);
-
-	/* we need the hex form of the interface IPv4 address */
-	$ip4arr = explode(".", $ip4address);
-	$hexwanv4 = "";
-	foreach($ip4arr as $octet)
-		$hexwanv4 .= sprintf("%02x", $octet);
 
 	/* we need the hex form of the broker IPv4 address */
-	$ip4arr = explode(".", $wancfg['gateway-6rd']);
-	$hexbrv4 = "";
-	foreach($ip4arr as $octet)
-		$hexbrv4 .= sprintf("%02x", $octet);
+	$hexbrv4 = return_hex_ipv4($wancfg['gateway-6rd']);
 	
 	/* binary presentation of the prefix for all 128 bits. */
-	$rd6prefixbin = "";
-	foreach($rd6arr as $element) {
-		$rd6prefixbin .= sprintf("%016b", hexdec($element));
-	}
+	$rd6prefixbin = convert_ipv6_to_128bit($rd6prefix);
+	
 	/* just save the left prefix length bits */
-	$rd6prefixstartbin = substr($rd6prefixbin, 0, $rd6prefixlen);
-
+	$rd6prefixbin = substr($rd6prefixbin, 0, $rd6prefixlen);
 	/* if the prefix length is not 32 bits we need to shave bits off from the left of the v4 address. */
-	$rd6brokerbin = substr(sprintf("%032b", hexdec($hexbrv4)), $v4prefixlen, 32);
-	$rd6brokerbin = str_pad($rd6prefixstartbin . $rd6brokerbin, 128, "0", STR_PAD_RIGHT);;
-
-	/* for the local subnet too. */
-	$rd6lanbin = substr(sprintf("%032b", hexdec($hexwanv4)), $v4prefixlen, 32);
-	$rd6lanbin = str_pad($rd6prefixstartbin . $rd6lanbin, 128, "0", STR_PAD_RIGHT);;
-
-	/* convert the 128 bits for the broker address back into a valid IPv6 address */ 
-	$rd6brarr = array();
-	$rd6brbinarr = array();
-	$rd6brbinarr = str_split($rd6brokerbin, 16);
-	foreach($rd6brbinarr as $bin)
-		$rd6brarr[] = dechex(bindec($bin));
-	$rd6brarr[7] = 1;
-	$rd6brgw = Net_IPv6::compress(implode(":", $rd6brarr));
+	$rd6prefixbin .= substr(sprintf("%032b", hexdec($hexbrv4)), $wancfg['prefix-6rd-v4plen'], 32);
+	/* fill out the rest with 0's */
+	$rd6prefixbin = str_pad($rd6prefixbin, 128, "0", STR_PAD_RIGHT);;
 
 	/* convert the 128 bits for the broker address back into a valid IPv6 address */ 
-	$rd6lanarr = array();
-	$rd6lanbinarr = array();
-	$rd6lanbinarr = str_split($rd6lanbin, 16);
-	foreach($rd6lanbinarr as $bin)
-		$rd6lanarr[] = dechex(bindec($bin));
-	$rd6lanpr = Net_IPv6::compress(implode(":", $rd6lanarr));
-	$rd6lanarr[7] = 1;
-	$rd6lan = Net_IPv6::compress(implode(":", $rd6lanarr));
+	$rd6brgw = convert_128bit_to_ipv6($rd6prefixbin);
 
 	/* setup the stf interface */
 	mwexec("/sbin/ifconfig srd0 destroy");
 	mwexec("/sbin/ifconfig srd0 create");
-	mwexec("/sbin/ifconfig srd0 v4plen {$v4prefixlen} pfix {$rd6prefix} plen {$rd6prefixlen} braddr {$wancfg['gateway-6rd']}");
-	mwexec("/sbin/ifconfig srd0 inet6 {$rd6lanpr} prefixlen 128");
+	mwexec("/sbin/ifconfig srd0 v4plen {$wancfg['prefix-6rd-v4plen']} pfix {$rd6prefix} plen {$rd6prefixlen} braddr {$wancfg['gateway-6rd']}");
 
-	log_error("Created 6rd interface srd0 v4plen {$v4prefixlen} pfix {$rd6prefix} plen {$rd6prefixlen} braddr {$wancfg['gateway-6rd']}");
-	log_error("Set IPv6 address inet6 {$rd6lanpr} prefixlen 128 for srd0");
-	
-	/* Example 6RD setup steps
-	# ifconfig srd0 create
-	# ifconfig srd0
-	srd0: flags=0<> metric 0 mtu 1280
-		srd: v4plen 0 pfix :: plen 0 braddr 0.0.0.0
-	# ifconfig srd0 up
-	# ifconfig srd0 v4plen 20 pfix fc00:0:0:1000:: plen 52 braddr 10.0.0.1
-	# ifconfig srd0
-		srd0: flags=1<UP> metric 0 mtu 1280
-		srd: v4plen 20 pfix fc00:0:0:1000:: plen 52 braddr 10.0.0.1
-	*/
+	log_error("Created 6rd interface srd0 v4plen {$wancfg['prefix-6rd-v4plen']} pfix {$rd6prefix} plen {$rd6prefixlen} braddr {$wancfg['gateway-6rd']}");
 
 	/* write out a default router file */
-	file_put_contents("{$g['tmp_path']}/{$wanif}_routerv6", "::1 -ifp srd0\n");
+	file_put_contents("{$g['tmp_path']}/{$wanif}_routerv6", "{$rd6brgw}\n");
+	file_put_contents("{$g['tmp_path']}/{$wanif}_defaultgwv6", "{$rd6brgw}\n");
 	
 	return 0;
 }
diff --git a/etc/inc/pfsense-utils.inc b/etc/inc/pfsense-utils.inc
index 7d5b458..a72c05a 100644
--- a/etc/inc/pfsense-utils.inc
+++ b/etc/inc/pfsense-utils.inc
@@ -2310,4 +2310,47 @@ function get_locale_list() {
 	asort($locales);
 	return $locales;
 }
+
+function return_hex_ipv4($ipv4) {
+	if(!is_ipaddrv4($ipv4))
+		return(false);
+	
+	/* we need the hex form of the interface IPv4 address */
+	$ip4arr = explode(".", $ipv4);
+	$hexwanv4 = "";
+	foreach($ip4arr as $octet)
+		$hexwanv4 .= sprintf("%02x", $octet);
+
+	return($hexwanv4);
+}
+
+function convert_ipv6_to_128bit($ipv6) {
+	if(!is_ipaddrv6($ipv6))
+		return(false);
+
+	$ip6arr = array();
+	$ip6prefix = Net_IPv6::uncompress($ipv6);
+	$ip6arr = explode(":", $ip6prefix);
+	/* binary presentation of the prefix for all 128 bits. */
+	$ip6prefixbin = "";
+	foreach($ip6arr as $element) {
+		$ip6prefixbin .= sprintf("%016b", hexdec($element));
+	}
+	return($ip6prefixbin);
+}
+
+function convert_128bit_to_ipv6($ip6bin) {
+	if(strlen($ip6bin) <> 128)
+		return(false);
+
+	$ip6arr = array();
+	$ip6binarr = array();
+	$ip6binarr = str_split($ip6bin, 16);
+	foreach($ip6binarr as $binpart)
+		$ip6arr[] = dechex(bindec($binpart));
+	$ip6addr = Net_IPv6::compress(implode(":", $ip6arr));
+
+	return($ip6addr);
+}
+
 ?>
diff --git a/etc/inc/services.inc b/etc/inc/services.inc
index d6c6a66..7a0b725 100644
--- a/etc/inc/services.inc
+++ b/etc/inc/services.inc
@@ -40,7 +40,7 @@
 */
 
 function strify($str) {
-   return '"' . $str . '"';
+	return '"' . $str . '"';
 };
 
 
@@ -86,11 +86,11 @@ function services_radvd_configure() {
 	foreach ($dhcpdv6cfg as $dhcpv6if => $dhcpv6ifconf) {
 		if(!isset($config['interfaces'][$dhcpv6if]['enable']))
 			continue;
-			
+								
 		/* are router advertisements enabled? */
 		if($dhcpv6ifconf['mode'] == "disabled")
 			continue;
-
+			
 		$realif = get_real_interface($dhcpv6if);
 
 		$ifcfgipv6 = get_interface_ipv6($dhcpv6if);
@@ -102,7 +102,7 @@ function services_radvd_configure() {
 		$subnetmaskv6 = gen_subnet_mask($ifcfgsnv6);
 
 		$radvdifs[] = $realif;
-
+		
 		$radvdconf .= "# Generated for DHCPv6 Server $dhcpv6if\n";
 		$radvdconf .= "interface {$realif} {\n";
 		$radvdconf .= "\tAdvSendAdvert on;\n";
@@ -174,9 +174,8 @@ function services_radvd_configure() {
 
 	/* handle DHCP-PD prefixes and 6RD dynamic interfaces */
 	foreach ($Iflist as $if => $ifdescr) {
-		if((!is_numeric($config['interfaces'][$if]['dhcp6-pd-sla-id'])) && (!is_numeric($config['interfaces'][$if]['prefix-6rd-id'])))
+		if(!isset($config['interfaces'][$if]['track6-interface']))
 			continue;
-
 		if(!isset($config['interfaces'][$if]['enable']))
 			continue;
 			
@@ -192,40 +191,16 @@ function services_radvd_configure() {
 		$ifcfgsnv6 = get_interface_subnetv6($if);
 		$subnetv6 = gen_subnetv6($ifcfgipv6, $ifcfgsnv6);
 		$subnetmaskv6 = gen_subnet_mask($ifcfgsnv6);
+		$trackif = $config['interfaces'][$if]['track6-interface'];
 		$radvdifs[] = $realif;
 
-		$autotype = "DHCP-PD";
-		/* 6rd on this interface? */
-		if(is_numeric($config['interfaces'][$if]['prefix-6rd-id'])) {
-			/* find the interface which has the 6RD prefix defined and it's IPv4 address */
-			foreach($Iflist as $rdif => $rdifdescr) {
-				if($config['interfaces'][$rdif]['ipaddrv6'] == "6rd") {
-					$realrdif = get_real_interface("$rdif");
-					$ip4address = find_interface_ip($realrdif);
-					log_error("radvd config found 6RD if {$rdif} address {$ip4address} for interface {$if}");
-					if((!is_ipaddrv4($ip4address)) || (is_private_ip($ip4address))) {
-						log_error("The interface IPv4 '{$ip4address}' address on interface '{$rdif}' is not public, not configuring 6RD prefix on {$if}");
-						// continue;
-					}
-					/* calculate the IPv6 prefix from the public IPv4 address */
-					$ip4arr = explode(".", $ip4address);
-					$rd6prefix = explode("/", $config['interfaces'][$rdif]['prefix-6rd']);
-					$rd6prefix = explode(":", $rd6prefix[0]);
-					$rd6lanprefixlen = 64;
-					$rd6lanprefix = sprintf("{$rd6prefix[0]}:{$rd6prefix[1]}:%02x%02x:%02x%02x::", $ip4arr[0], $ip4arr[1], $ip4arr[2], $ip4arr[3]);
-					$ifcfgsnv6 = "{$rd6lanprefixlen}";
-					$subnetv6 = "{$rd6lanprefix}";
-					$autotype = "6rd";
-					break;
-				}
-			}
-		}
-		
-		log_error("configuring interface {$if} for type {$autotype} radvd subnet {$subnetv6}/{$ifcfgsnv6}");
+		$autotype = $config['interfaces'][$trackif]['ipaddrv6'];
+	
+		log_error("configuring RA on {$if} for type {$autotype} radvd subnet {$subnetv6}/{$ifcfgsnv6}");
 
 		$dnslist = array();
 		if(is_ipaddrv6($subnetv6)) {
-			$radvdconf .= "# Generated for DHCP-PD delegation $if\n";
+			$radvdconf .= "# Generated config for {$autotype} delegation from {$trackif} on {$if}\n";
 			$radvdconf .= "interface {$realif} {\n";
 				$radvdconf .= "\tAdvSendAdvert on;\n";
 				$radvdconf .= "\tMinRtrAdvInterval 3;\n";
diff --git a/usr/local/www/interfaces.php b/usr/local/www/interfaces.php
index b0594df..6435ea6 100755
--- a/usr/local/www/interfaces.php
+++ b/usr/local/www/interfaces.php
@@ -223,6 +223,11 @@ switch($wancfg['ipaddrv6']) {
 	case "6to4":
 		$pconfig['type6'] = "6to4";
 		break;
+	case "track6":
+		$pconfig['type6'] = "track6";
+		$pconfig['track6-interface'] = $wancfg['track6-interface'];
+		$pconfig['track6-prefix-id'] = $wancfg['track6-prefix-id'];
+		break;
 	case "6rd":
 		$pconfig['prefix-6rd'] = $wancfg['prefix-6rd'];
 		if($wancfg['prefix-6rd-v4plen'] == "")
@@ -237,8 +242,6 @@ switch($wancfg['ipaddrv6']) {
 			$pconfig['ipaddrv6'] = $wancfg['ipaddrv6'];
 			$pconfig['subnetv6'] = $wancfg['subnetv6'];
 			$pconfig['gatewayv6'] = $wancfg['gatewayv6'];
-			$pconfig['dhcp6-pd-sla-id'] = $wancfg['dhcp6-pd-sla-id'];
-			$pconfig['prefix-6rd-id'] = $wancfg['prefix-6rd-id'];
 		} else
 			$pconfig['type6'] = "none";
 		break;
@@ -507,6 +510,11 @@ if ($_POST['apply']) {
 			if (in_array($wancfg['ipaddrv6'], array()))
 				$input_errors[] = sprintf(gettext("You have to reassign the interface to be able to configure as %s."),$_POST['type']);
 			break;
+		case "track6":
+			/* needs to check if $track6-prefix-id is used on another interface */
+			if (in_array($wancfg['ipaddrv6'], array()))
+				$input_errors[] = sprintf(gettext("You have to reassign the interface to be able to configure as %s."),$_POST['type']);
+			break;
 	}
 
 	
@@ -644,13 +652,13 @@ if ($_POST['apply']) {
 		unset($wancfg['subnetv6']);
 		unset($wancfg['gatewayv6']);
 		unset($wancfg['dhcphostname']);
-		unset($wancfg['dhcp6-pd-sla-id']);
 		unset($wancfg['dhcp6-duid']);
 		unset($wancfg['dhcp6-ia-pd-len']);
+		unset($wancfg['track6-interface']);
+		unset($wancfg['track6-prefix-id']);		
 		unset($wancfg['prefix-6rd']);
 		unset($wancfg['prefix-6rd-v4plen']);
 		unset($wancfg['gateway-6rd']);
-		unset($wancfg['prefix-6rd-id']);
 		unset($wancfg['pppoe_password']);
 		unset($wancfg['pptp_username']);
 		unset($wancfg['pptp_password']);
@@ -676,21 +684,31 @@ if ($_POST['apply']) {
 		/* for dynamic interfaces we tack a gateway item onto the array to prevent system
 		 * log messages from appearing. They can also manually add these items */
 		/* 1st added gateway gets a default bit */
-		/* FIXME: Add address family check here! */
+		/* FIXME: Add address family check here! IPv6 needs a gateway bit too */
 		if(!empty($a_gateways)) {
 			$gateway_item = array();
 			/* check for duplicates */
 			$skip = false;
 			foreach($a_gateways as $item) {
-				if(($item['interface'] == "$if") && (preg_match("/dynamic/", $item['gateway']))) {
-					$skip = true;
+				if(($item['interface'] == "$if") && (trim($item['gateway']) == "dynamic")) {
+					$skip4 = true;
+				}
+				if(($item['interface'] == "$if") && (trim($item['gateway']) == "dynamic6")) {
+					$skip6 = true;
 				}
 			}
-			if($skip == false) {
+			if($skip4 == false) {
 				$gateway_item['gateway'] = "dynamic";
-				$gateway_item['descr'] = sprintf(gettext("Interface %s dynamic gateway"),$if);
+				$gateway_item['descr'] = sprintf(gettext("Interface %s dynamic IPv4 gateway"),$if);
 				$gateway_item['name'] = "GW_" . strtoupper($if);
 				$gateway_item['interface'] = "{$if}";
+				$gateway_item['family'] = "inet";
+			} elseif($skip6 == false) {
+				$gateway_item['gateway'] = "dynamic6";
+				$gateway_item['descr'] = sprintf(gettext("Interface %s dynamic IPv6 gateway"),$if);
+				$gateway_item['name'] = "GW_" . strtoupper($if) ."_v6";
+				$gateway_item['interface'] = "{$if}";
+				$gateway_item['family'] = "inet6";
 			} else {
 				unset($gateway_item);
 			}
@@ -801,8 +819,6 @@ if ($_POST['apply']) {
 			case "staticv6":
 				$wancfg['ipaddrv6'] = $_POST['ipaddrv6'];
 				$wancfg['subnetv6'] = $_POST['subnetv6'];
-				$wancfg['dhcp6-pd-sla-id'] = $_POST['dhcp6-pd-sla-id'];
-				$wancfg['prefix-6rd-id'] = $_POST['prefix-6rd-id'];
 				if ($_POST['gatewayv6'] != "none") {
 					$wancfg['gatewayv6'] = $_POST['gatewayv6'];
 				}
@@ -827,6 +843,11 @@ if ($_POST['apply']) {
 			case "6to4":
 				$wancfg['ipaddrv6'] = "6to4";
 				break;
+			case "track6":
+				$wancfg['ipaddrv6'] = "track6";
+				$wancfg['track6-interface'] = $_POST['track6-interface'];
+				$wancfg['track6-prefix-id'] = $_POST['track6-prefix-id'];
+				break;
 			case "none":
 				break;
 		}
@@ -1079,7 +1100,7 @@ $statusurl = "status_interfaces.php";
 $closehead = false;
 include("head.inc");
 $types4 = array("none" => gettext("None"), "staticv4" => gettext("Static IPv4"), "dhcp" => gettext("DHCP"), "ppp" => gettext("PPP"), "pppoe" => gettext("PPPoE"), "pptp" => gettext("PPTP"), "l2tp" => gettext("L2TP") /* , "carpdev-dhcp" => "CarpDev"*/);
-$types6 = array("none" => gettext("None"), "staticv6" => gettext("Static IPv6"), "dhcp6" => gettext("DHCP6"), "6rd" => gettext("6rd"), "6to4" => gettext("6to4"));
+$types6 = array("none" => gettext("None"), "staticv6" => gettext("Static IPv6"), "dhcp6" => gettext("DHCP6"), "6rd" => gettext("6rd"), "6to4" => gettext("6to4"), "track6" => gettext("Track Interface"));
 
 ?>
 
@@ -1126,23 +1147,27 @@ $types6 = array("none" => gettext("None"), "staticv6" => gettext("Static IPv6"),
 	function updateTypeSix(t) {
 		switch(t) {
 			case "none": {
-				jQuery('#staticv6, #dhcp6, #6rd, #6to4').hide();
+				jQuery('#staticv6, #dhcp6, #6rd, #6to4, #track6').hide();
 				break;
 			}
 			case "staticv6": {
-				jQuery('#none, #dhcp6, #6rd, #6to4').hide();
+				jQuery('#none, #dhcp6, #6rd, #6to4, #track6').hide();
 				break;
 			}
 			case "dhcp6": {
-				jQuery('#none, #staticv6, #6rd, #6to4').hide();
+				jQuery('#none, #staticv6, #6rd, #6to4, #track6').hide();
 				break;
 			}
 			case "6rd": {
-				jQuery('#none, #dhcp6, #staticv6, #6to4').hide();
+				jQuery('#none, #dhcp6, #staticv6, #6to4, #track6').hide();
 				break;
 			}
 			case "6to4": {
-				jQuery('#none, #dhcp6, #staticv6, #6rd').hide();
+				jQuery('#none, #dhcp6, #staticv6, #6rd, #track6').hide();
+				break;
+			}
+			case "track6": {
+				jQuery('#none, #dhcp6, #staticv6, #6rd, #6to4').hide();
 				break;
 			}
 		}
@@ -1621,63 +1646,6 @@ $types6 = array("none" => gettext("None"), "staticv6" => gettext("Static IPv6"),
 											</div>
 										</td>
 									</tr>
-									<tr>
-										<td width="22%" valign="top" class="vncell"><?=gettext("DHCPv6 Prefix Delegation ID"); ?></td>
-										<td width="78%" class="vtable">
-											<select name="dhcp6-pd-sla-id" class="formselect" id="dhcp6-pd-sla-id">
-												<?php
-												// Needs to check if the ID is not used on another interface
-												foreach($ifdescrs as $pdif => $pddescr) {
-													if(is_numeric($config['interfaces'][$pdif]['dhcp6-ia-pd-len'])) {
-														$pdlen = $config['interfaces'][$pdif]['dhcp6-ia-pd-len'];
-														continue;
-													}
-												}
-												
-												if($pconfig['dhcp6-pd-sla-id'] == "none")
-													$selected = "selected";
-												echo "<option value=\"none\" {$selected}>". gettext("None") ."</option>\n";
-												$numbers = pow(2, $pdlen);
-												for($i = 0;$i < $numbers; $i++) {
-													echo "<option value=\"{$i}\" ";
-													if ("$i" == $pconfig['dhcp6-pd-sla-id']) {
-														echo "selected";
-													}
-													echo ">" . dechex($i) . "</option>";
-												}
-												?> 
-											</select>
-											<?=gettext("This ID sets the delegated DHCP-PD prefix number which will be used to setup the interface.");?>
-										</td>
-									</tr>
-									<tr>
-										<td width="22%" valign="top" class="vncell"><?=gettext("6RD Rapid Deployment network ID"); ?></td>
-										<td width="78%" class="vtable">
-											<select name="prefix-6rd-id" class="formselect" id="prefix-6rd-id">
-												<?php
-												// Needs to check if the ID is not used on another interface
-												foreach($ifdescrs as $rdif => $rddescr) {
-													if(is_numeric($config['interfaces'][$rdif]['prefix-6rd-v4plen'])) {
-														$rdlen = $config['interfaces'][$rdif]['prefix-6rd-v4plen'];
-														continue;
-													}
-												}
-												if($pconfig['prefix-6rd-id'] == "none")
-													$selected = "selected";
-												echo "<option value=\"none\" {$selected}>". gettext("None") ."</option>\n";
-												$numbers = pow(2, $rdlen);
-												for($i = 0;$i < $numbers; $i++) {
-													echo "<option value=\"{$i}\" ";
-													if ("$i" == $pconfig['prefix-6rd-id']) {
-														echo "selected";
-													}
-													echo ">" . dechex($i) . "</option>";
-												}
-												?> 
-											</select>
-											<?=gettext("This ID sets the 6RD network prefix which will be used to setup the interface.");?>
-										</td>
-									</tr>
 								</table>
 							</td>
 						</tr>
@@ -1736,6 +1704,7 @@ $types6 = array("none" => gettext("None"), "staticv6" => gettext("Static IPv6"),
 									<tr>
 										<td colspan="2" valign="top" class="listtopic"><?=gettext("DHCP6 client configuration"); ?></td>
 									</tr>
+									<!--- Leave commented out for now
 									<tr>
 										<td width="22%" valign="top" class="vncell"><?=gettext("DHCPv6 Unique Identifier (DUID)"); ?></td>
 										<td width="78%" class="vtable">
@@ -1751,6 +1720,7 @@ $types6 = array("none" => gettext("None"), "staticv6" => gettext("Static IPv6"),
 											
 										</td>
 									</tr>
+									-->
 									<tr>
 										<td width="22%" valign="top" class="vncell"><?=gettext("DHCPv6 Prefix Delegation size"); ?></td>
 										<td width="78%" class="vtable">
@@ -1814,6 +1784,91 @@ $types6 = array("none" => gettext("None"), "staticv6" => gettext("Static IPv6"),
 								</table>
 							</td>
 						</tr>
+						<tr style="display:none;" name="track6" id="track6">
+							<td colspan="2" style="padding: 0px;">
+								<table width="100%" border="0" cellpadding="6" cellspacing="0">
+									<tr>
+										<td colspan="2" valign="top" class="listtopic"><?=gettext("Track IPv6 Interface"); ?></td>
+									</tr>
+									<tr>
+										<td width="22%" valign="top" class="vncell"><?=gettext("IPv6 Interface"); ?></td>
+										<td width="78%" class="vtable">
+										<select name='track6-interface' class='formselect' >
+										<?php 
+											$interfaces = get_configured_interface_with_descr(false, true);
+											$dynv6ifs = array();
+											foreach ($interfaces as $iface => $ifacename) {
+												switch($config['interfaces'][$iface]['ipaddrv6']) {
+													case "6to4":
+													case "6rd":
+													case "dhcp6":
+														$dynv6ifs[$iface] = $ifacename;
+														break;
+													default:
+														continue;
+												}
+											}
+											foreach($dynv6ifs as $iface => $ifacename) {
+												echo "<option value=\"{$iface}\"";
+												if ($iface == $pconfig['track6-interface'])
+													echo " selected";
+												echo ">" . htmlspecialchars($ifacename) . "</option>";
+											}
+										  ?>
+										</select> <br>
+											<br>
+											<?=gettext("This selects the dynamic IPv6 WAN interface to track for configuration") ?><br />
+										</td>
+									</tr>
+									<tr>
+										<td width="22%" valign="top" class="vncell"><?=gettext("IPv6 Prefix ID"); ?></td>
+										<td width="78%" class="vtable">
+											<select name="track6-prefix-id" class="formselect" id="track6-prefix-id">
+												<?php
+												/* DHCP-PD is variable, calculate from the prefix-len on the WAN interface */
+												/* 6rd is variable, calculate from 64 - (v6 prefixlen - (32 - v4 prefixlen)) */
+												/* 6to4 is 16 bits, e.g. 65535 */
+												
+												switch($config['interfaces'][$pconfig['track6-interface']]['ipaddrv6']) {
+													case "6to4":
+														$pdlen = 16;
+														break;
+													case "6rd":
+														$rd6cfg = $config['interfaces'][$pconfig['track6-interface']];
+														$rd6plen = explode("/", $rd6cfg['prefix-6rd']);
+														$pdlen = (64 - ($rd6plen[1] + (32 - $rd6cfg['prefix-6rd-v4plen'])));
+														break;
+													case "dhcp6":
+														$dhcp6cfg = $config['interfaces'][$pconfig['track6-interface']];
+														$pdlen = $dhcp6cfg['dhcp6-ia-pd-len'];
+														break;
+													default:
+														$pdlen = 0;
+														break;
+												}
+												print_r($pconfig['track6-interface']);
+												if($pconfig['track6-prefix-id'] == "none")
+													$selected = "selected";
+												echo "<option value=\"none\" {$selected}>". gettext("None") ."</option>\n";
+												$numbers = pow(2, $pdlen);
+												for($i = 0;$i < $numbers; $i++) {
+													echo "<option value=\"{$i}\" ";
+													if ("$i" == $pconfig['track6-prefix-id']) {
+														echo "selected";
+													}
+													echo ">" . dechex($i) . "</option>\n";
+												}
+												?> 
+											</select>
+											<?=gettext("The value in this field is the (Delegated) IPv6 prefix id. This determines the configurable network ID based on the dynamic IPv6 connection"); ?>
+										</td>
+									</tr>
+										</td>
+									</tr>
+									
+								</table>
+							</td>
+						</tr>
 						<tr style="display:none;" name="ppp" id="ppp">
 							<td colspan="2" style="padding: 0px;">
 								<table width="100%" border="0" cellpadding="6" cellspacing="0">